: 1986 Fleetwood Brougham MPG



cadillac_jim
12-18-09, 04:46 PM
Ok, so I inherited this car. It runs good, only has 63,xxxx miles on it. But the thing is eating gas, like 10mpg. I know it's an Olds 307 v8, but everyone is telling me it should be decent on gas. So, I changed the plugs, wires, coil, etc and it runs better. But now it seems to chug while idling and sometimes it'll diesel on me when I turn it off (motor keeps running for a few cylinder compressions). I had a friend look at it, he's a mechanic at a dealership, and he noticed that the carburetor is letting some gas out around the front (think he said the pumper, not sure though) and that the "fuel enrichment solenoid" was unplugged. He told me not to plug it back in because the carburetors are junk on these vehicles and it's probably unplugged for a reason. His advice was to either drive it or buy an aftermarket carburetor, Edelbrock etc, and put it on and disconnect of most of the emission vacuum lines etc. I'm not sure what to do here or if the carburetor is even the reason for the bad MPG. I'm thinking the timing is off and it maybe running rich. The check engine light is also on, I have another friend who thinks he can scan it or manually get the codes to see why it's on. I've worked on a lot of cars, but not many with carburetors, especially electronic carburetors. Anybody have any advice? Thanks in advance.

outsider
12-18-09, 05:08 PM
my olds 307 powered '87 gets ~18 mpg

I'm sure most people here will tell you that the stock carbs are decent. Yours may need a rebuild if it's leaking gas. I would have the carb looked at, could have been modified/rejetted/gummed up, who knows.

sven914
12-18-09, 05:20 PM
The first thing you have to do is scan the computer for codes. In the OBD-I reference thread (http://www.chicagocarexchange.com/resize.asp?image=PC205pside.JPG&size=800), my post (#7) gives information on how to scan your car.

Other things to check are the Air Cleaner Damper door (THERMAC) operation, Air Filter for clogging, the Vacuum Hoses for leaks, splits, and correct roughing (as seen on the Emission Control Label), Ignition Timing, Electronic Spark Timing (EST) for correct operation, Transmission Torque Converter Clutch (TCC) for correct operation, and check for a restricted exhaust system.

Putting on an after market carburettor may solve your immediate problem, but the engine will never meet the factory fuel economy.

The problem could also be a dirty carburetor and pistons covered in carbon build up. I would recommend using Gumout with Regane (http://www.google.com/products?hl=en&source=hp&q=Gumout+with+regane&um=1&ie=UTF-8&ei=1fIrS4nmOpC4M9LO9P0I&sa=X&oi=product_result_group&ct=title&resnum=3&ved=0CCAQrQQwAg) on your next fill up (you can get it at any part's store/Wal-Mart) and/or using Sea Foam motor treatment (http://www.seafoamsales.com/) to clean the carburettor and engine.

cadillac_jim
12-18-09, 05:21 PM
Ya, that is what I was thinking. I'm getting different opinions from people though. Basically I was going to keep this car as my daily driver, but I need to figure out this MPG problem. The carburetor is clean and as far as I know it has only had premium gas ran through it. I'm want to just plug the solenoid back in, but I'm afraid it'll screw the whole thing up then. Not sure what to do yet.

cadillac_jim
12-18-09, 05:35 PM
I ran a can of Seafoam through the gas. I haven't ran any through the carburetor or brake booster vacuum line yet. I've never used Gumout, I'lltry it.

sven914
12-18-09, 05:47 PM
Try the Sea Foam through the Carburettor, it's more consecrated so it works better.

That solenoid that's unplugged, which side of the engine is it on? If it's on the driver's side and it toward the front, then it is the Throttle Position Sensor. If it is on the passenger side, then it Is the Mixture Control Solenoid. If the mixture control solenoid is unplugged, then it goes to it default position; Full Rich. It'll come up as code 23 if the MC is unplugged and 21 if the TPS is unplugged.

The mixture control solenoid plug keeps falling out on my car (I have it zip-tied in place), so it could have done the same thing to your's. Plug it in and see what happens.

cadillac_jim
12-18-09, 06:02 PM
Ok, I'll give it a whirl. I'm assuming it's the "Mixture Control Solenoid" because he called it a "fuel enrichment solenoid". I'd go look at it now, but I'm at work. Would it be a good idea to run the Seafoam through the carb and brake booster line?

sven914
12-18-09, 06:18 PM
I ran it through the carburettor, but didn't stall the engine out. Let the engine warm up to operating temperature and then you're going to need someone to hold the RPM's up a little while you pour half a can in the carburettor, and then you're going to need to drive the car for about a half hour to clear the engine.

MudAnt
12-18-09, 06:19 PM
I have the same car with the same problem (Check engine light on, low MPG). If you manage to fix it, partially or even back to the stock MPG, be sure to post what you did here!

cadillac_jim
12-18-09, 06:30 PM
Sure can.


A guy here at work told me to try something like this:

"The best way to clean carbon build-up out of your engine is NOT to take the car out and run it as hard as you can. This only results in meetings with local law enforcement personnel, and doesn't do much for cleaning out carbon.
If you really want to clean the carbon out of your engine follow these simple steps. Fill an empty soda bottle with water. Remove your air cleaner. Start your engine. While using one hand to control the throttle, trickle the water into the carb or throttle body with the other while holding your thumb over the bottle opening. Keep the engine rpm's up so that the engine doesn't die. Make sure that you don't pour the water in too fast! Water doesn't compress and if you pour too much water in, severe engine damage can result! White smoke from the exhaust is normal. If you have a port fuel injected car, you obviously won't be able to use this method, but I have had success with connecting a vacuum hose to a port at the base of the throttle body and sticking the other end of the hose into the bottle of water. The vacuum of the engine will suck the water in, creating the same effect. This will clean out even the most stubborn carbon, by 'steam cleaning' your cylinders."

Or to run transmission fluid through the carb and brake booster line. This guy knows about cars, but he's kind of a hillbilly, so sometime his "methods" scare me.... Would any of this work?

sven914
12-18-09, 07:15 PM
I don't know about transmission fluid but I've steamed cleaned the engine, using the method you described, and it worked somewhat. But the problem (rough idle, misfire, and dieseling/run-on) came back a few days later. The Sea Foam follows the same method of introducing the stuff into the intake, but the problem stayed away for over a month. Also it's kind of awkward to use one hand to increase the RPMs while trickling a specific amount of fluid into the engine with the other (plus the engine has to be warm so your hand can get pretty hot).

RocketFast321
12-18-09, 07:53 PM
t the "fuel enrichment solenoid" was unplugged. He told me not to plug it back in because the carburetors are junk on these vehicles and it's probably unplugged for a reason. His advice was to either drive it or buy an aftermarket carburetor, Edelbrock etc, and put it on and disconnect of most of the emission vacuum lines etc.

Your car is in loop mode, with the Mixture Control Solenoid not hook up it will drink gas. If you did put a Edelbrock on it, you will have to replace your CCC distributor to a vac advance one. The q-jet is a great carb. The main venturis are small and give you good MPG. Hit it to the floor and the huge secondary venturis open up. And most were 750cfm.

cadillac_jim
12-18-09, 08:03 PM
If the solenoid is bad, how hard/much is that to replace? Sorry I haven't had much experience with carbs.

cadillac_jim
12-18-09, 08:24 PM
I'm assuming this would be the rebuild kit I would need: http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=230399384080&crlp=1_263602_263622&ff4=263602_263622&viewitem=&guid=a43865521250a03664813a91ffd63bfd&rvr_id=&ua=WVF%3F&itemid=230399384080

sven914
12-18-09, 09:23 PM
Yeah thats the right one.

cadillac_jim
12-18-09, 10:49 PM
I may as well get this too: http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=280439433874&category=33551&_trksid=p4340.m263&_trkparms=algo%3DSI%26its%3DI%252BC%26itu%3DUCI%26 otn%3D10%26ps%3D63

cadillac_jim
12-19-09, 02:16 AM
Ok, so I just got home from work. The solenoid that was unplugged was on the passenger side, so it's the Mixture Control Solenoid. I plugged it in and started it and it just instantly died, then wouldn't even attempt to start. It just turned over. Does this mean to just replace the solenoid, or is there a bigger problem?


There was also another plug that wasn't plugged into anything and I couldn't find what it would got to. It was a green plug with a clip, it didn't have a rubber shrouding on it like the one for the Mixture Control Solenoid. It was taped over, so maybe it is for an option I don't have?

Thanks for all the help.

sven914
12-19-09, 02:29 AM
The green plug is a test port and is supposed to be unplugged (it don't go anywhere).

Plugging the solenoid in probably forced the mixture too lean, so the solenoid probably is bad. But the idle adjustment might also be messed up.

cadillac_jim
12-19-09, 03:20 AM
So how do I fix the Idle adjustment, if that too is messed up?

cadillac_jim
12-19-09, 03:34 AM
Also, it idles rough. It "chugs" while at a stop.

sven914
12-19-09, 11:42 AM
Chugging can be caused by anything from vacuum leaks, to off timing, to poor float adjustment, to contaminated gasoline.

I looked in my service manual and found very little information on idle adjustments. I found a description of the Mixture Control Solenoid that said it is pulsed on and off ten times per second, and then when it's getting power, it forces the mixture Lean. There are adjustments for the Mixture Control Solenoid, the Idle Mixture Needles, and the Air Bleed Valve in my manual, but they are really vague. They don't mention any special tool, but I know you need a gauge, gauge (to determine the proper spacing) and that you need a 6 cylinder dwell meter to see what the computer is doing (you use the green plug and turn the idle screw to obtain a dwell of 25*).

These computer controlled carburettors are not user friendly. To change the Mixture Control Solenoid, you need have two special GM adjusting tools. Being that you're not fluent in carburettors, I recommend you take your car to a GM dealership and have them professionally diagnose the problem and replace the Mixture Control Solenoid.

cadillac_jim
12-19-09, 02:01 PM
I'm just going to change the solenoid myself, looks easy enough, then if it still acts funny or won't run when it's plugged in I'll take it to a shop.

jayoldschool
12-19-09, 04:41 PM
I recommend you take your car to a GM dealership and have them professionally diagnose the problem and replace the Mixture Control Solenoid.

lol, most GM techs will have NEVER worked on a carb before!

cadillac_jim
12-19-09, 04:52 PM
And it seems like most I've talked to think that this model carb is junk and not worth messing with. They must teach this now in the ASE Certified classes.....

cadillac_jim
12-19-09, 05:04 PM
I called one shop today and the guy actually told me, "If you got it running, I wouldn't even mess with it. They're not worth it." This car only has 60 some thousand miles on it. I plan on keeping it. I talked to a guy here in town who knows about the car and he told me that it probably quit running and a local mechanic just unplugged the solenoid because the owner wouldn't know the difference.

RocketFast321
12-19-09, 09:06 PM
And it seems like most I've talked to think that this model carb is junk and not worth messing with. They must teach this now in the ASE Certified classes.....

It's a very good carb. You just have tune it. Their are alot of videos on youtube to help you. If put your in test mode to read codes it should be clicking while the car is reading out codes. Also on my 84 electra i have 2 ECM fuses. See if your car has both, and of course make sure both are good

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sven914
12-20-09, 01:14 AM
Here is the procedure for changing the solenoid (procedure begins with the solenoid plunger removed):

1. Remove the air horn and gasket

2. Remove the solenoid connector attaching screws

3. Remove solenoid adjusting screw using J-tool 28696-10

4. Remove the primary metering rods and springs

5. Remove the float bowl

6. Remove the Mixture Control Solenoid

Make Mixture Control Solenoid adjustment using the following procedure (found the specific procedure in my book):

1. Position J-tool 33815-1 (gage) over the throttle side of metering rod jet guide and temporarily install solenoid plunger

2. Install solenoid adjusting screw and rich limit stop (engage the first 6 screw threads)

3. Hold the solenoid plunger down. Use J-28696-10 to turn the solenoid adjusting screw in or out, until plunger contacts both the solenoid stop and gage

4. Turn screw inward, counting turns to the bottom

5. Remove solenoid adjusting screw, rich limit stop, solenoid plunger, and gage

6. Install float bowl

7. Install primary metering rods (do not force them; damage can result)

8. Install solenoid plunger, solenoid adjusting screw, and rich limit stop

9. Use J-28696-10 to turn the screw inward to bottom. Back out number of turns counted in step 4

10. Install air horn with new gasket

Following a Mixture Control Solenoid replacement/adjustment, the Air Bleed Valve must be adjusted. The procedure is a s follows

1. Insert J-33815-2 gaging tool through air horn vent hole, to contact solenoid plunger. Locate upper end of gage over cavity next to valve

2. Hold gage down, so plunger is against solenoid stop, then rotate gage toward the valve. Turn valve in or out until gage contacts top of valve

3. Remove gage

4. Check idle mixture with the engine running

Idle mixture check Procedure is as follows:

1. Set parking brake and block drive wheels

2. Remove the air cleaner and plug the vacuum lines to the THERMAC

3. Connect a tachometer to the distributor and a dwell meter to the green M/C solenoid dwell connector

4. Check ignition timing and adjust if necessary (ask me for the procedure later; I'm tired of typing)

5. Disconnect and plug canister purge hose at canister

6. With engine running and at operating temperature, transmission in drive, and AC OFF, observe idle dwell. It should be between 10 and 50 degrees and varying. If idle dwell is fixed below 10 or above 50, STOP and determine cause of lean of rich condition. Adjust idle mixture if necessary (ask me for it)

7. If idle dwell is varying between 10 and 50 adjust the Idle Load Compensator if necessary (ask me for the procedure)

8. Reconnect all vacuum hoses and install air cleaner

cadillac_jim
12-20-09, 02:52 AM
After talking to a few different mechanics, I've come to the conclusion that I should just buy a new/rebuilt carb. It'll be cheaper and probably the better option. I connected the solenoid again today to see if I could hear it cycle and I couldn't. After I told one of the mechanics this, he told me basically it's hard to find someone who knows how to work on these anymore and someone that has the proper gauges and tools. He also recommended just buying a carb. He said they come already pre-set and all you need to do it put it on and it's ready to go. I'll keep everyone updated. Thanks.

cadillac_jim
12-20-09, 02:54 AM
Forgot to mention that I found a few carburetors on ebay for around $230.

sven914
12-20-09, 11:11 AM
Is it a stock Rochester? And are you sure it's for your engine?

After market carburettors like Edelbrock are for performance applications, so they dump fuel don't have enough vacuum ports to service your needs. Rochester's from Chevrolet engines have the fuel inlet coming in at a 90 degree bend and are not compatible with the 307.

Around where I live, there are a few carburettor repair shops, who quoted me about $150 for a rebuild. Maybe if you Google "carburettor repair" with your zip code, you can find a few places that will work on your carburettor.

cadillac_jim
12-20-09, 01:41 PM
Here's the email I sent him and the reply he gave me.

Me:
"I have a 1986 Cadillac Fleetwood Brougham with a v8 307. Do you have a carb for this car? And does it have new Mixture Control and Throttle Positioning Solenoids?"
Reply:
"Yes we have the correct carburetor for your vehicle. We use rebuilt mixture control solinoids (look and function the same as new) and the tps is brand new. The cost is $210.00 exchange plus shipping."

And in his description he has:

"I ALSO HAVE THE COMPUTERIZED CARB FOR THE 1981-90 BUICK,CADILLAC,OLDS w/ A 307 ENGINE CLIMATIC CHOKE AND STRAIGHT INLET."

"This carburetor has been completely disassembled ,cleaned, well plugs epoxied to prevent leak down, primary throttle shaft is bushed, base is resurfaced, and then the carburetor is reassembled with new parts; tps,filter, electric choke,accelerator pump,gaskets and set to oem specs. Comes with a & FREE mounting and air cleaner gasket. "

What do you think?

cadillac_jim
12-20-09, 03:07 PM
Good idea Sven914, found a shop that deals with carburetors a lot. He knew exactly what carb I was talking about and said he does them all the time. Said he completely tears them down, cleans, new seals, brass bushings?, gaskets, needles, springs, float, and new Mixture Control and I think he said throttle positioning sensor for $320. Thinking this is the best I've found so far.

priscillabrougham
12-20-09, 05:46 PM
If you've never done a rebuild yourself, it's tricky. Before taking a screwdriver to it, sven914 is right, I would check all vacuum lines. Take your time, and follow the chart in front of the radiator. It looks menacing, but a drink or two in, and you'll have it all figured out. This includes the vacuum line into the MAP sensor. This one is often overlooked because it looks like an electrical line, and is running through an electrical line plastic shroud thing, but it is a vacuum line. A malfunctioning MAP will set code 34 on the ECM.

What will not set a code is a malfunctioning AIR system. I'd also check this system for proper operation. If the pump is moving freely (it's the one under the A/C compressor), be sure that the AIR divert solenoid is plugged in, and the AIR vacuum line is plugged in. If you need photos, let me know. A non-operational AIR valve will lower fuel economy at idle and wide open throttle.

Vacuum is so crucial to these cars running right, that a leak anywhere in the system could jeopardize fuel economy. I've heard of these cars idling rough because the vacuum line attached to the parking brake leaked (seriously).

Another quick check is the fuel filter. They often come with a rubber gasket and a small white clip thing in the middle. This kind of slows the gas down entering the carburetor. If it's never been changed, that gasket is likely to be rotted out, dumping more fuel than necessary into the carburetor.

If you're still gunshy on the rebuild, look up Doc Patten Carburetors in Ardmore, AL. I surely wasn't about to risk dissecting mine, as it is my daily driver. It cost me about $200 to get mine rebuilt, but he does good work. Granted, you can buy a rebuilt one for about $50 more, but I guess I'm into salvaging what I have (despite it costing more). He can rebuild it, and even re-jet it slightly to eek out another half a mile a gallon.

cadillac_jim
12-20-09, 06:16 PM
"What will not set a code is a malfunctioning AIR system. I'd also check this system for proper operation. If the pump is moving freely (it's the one under the A/C compressor), be sure that the AIR divert solenoid is plugged in, and the AIR vacuum line is plugged in. If you need photos, let me know. A non-operational AIR valve will lower fuel economy at idle and wide open throttle."

Pictures would be helpful.

I talked to the guy who formerly owned the car, he said he just had all the vacuum lines and coolant lines replaced. I'm just taking the car in tomorrow to get the car completely rebuilt. From what I've heard this guy is good and has done it for years, opened his shop in 1973. It's a little bit of a drive, but I want to know it's done right. I'll check the vacuum lines out, but from what I've seen they all looked fine. Even the metal tube that connects to the air breather is new.

When the "new" carb is put on will the check engine light go off, if that's the only reason it's on for?

Thanks for all the responses, it's nice to be able to get advice from people who know about these cars. Thanks again.

priscillabrougham
12-20-09, 07:01 PM
Well, first off, if the check engine light is on, then we need to determine which code is set. This will save you a whole lot of time and money!

To do this, get a paper clip, straighten it out, then bend it in half like a U. Then, with the car OFF, insert the paper clip to jumper terminals A & B on the ECM plug under the dashboard, as seen in the photos:

http://www.marcofrattarelli.com/photos/ecm plug very far.jpg
http://www.marcofrattarelli.com/photos/ecm plug close.jpg
http://www.marcofrattarelli.com/photos/ecm plug very close.jpg

With the paper clip in place, turn the key to ON (don't start the car). The "Check Engine" light will flash the codes you have in the computer.

Picture morse code with a two digit number. The first three times it does this it will flash once, then twice, once, then twice, once, then twice. This is code 12, indicating the system is properly operating. After this, the light will flash the first digit then the second digit three times for what ever code is in there. Each code will flash three times. At the end of the trouble codes, it will flash 1-2 three times again.

Turn the key off, remove the paper clip, and tell us which codes flashed. I can then tell you what's up with the system.

I took a whole lot more photos, but check this out first and we'll go from there.

cadillac_jim
12-20-09, 07:15 PM
Just write the flashes down then?

priscillabrougham
12-20-09, 07:25 PM
Yes, just write them down, then post them. I have a service manual for a 1988 Brougham, but the codes are most likely the same since it is the same drivetrain as your '86. I'll be able to look up the codes and tell you what they indicate. If for nothing else, you can go into the shop with an idea of what's going on.

RocketFast321
12-20-09, 07:46 PM
Just write the flashes down then?

The first 3 codes will be 12:
Flash.....Flash-Flash.......Flash......Flash-Flash......Flash.........Flash-Flash.

cadillac_jim
12-21-09, 03:42 PM
It gave me a code:

23 intake air temp sensor out of range, low

45 oxygen sensor rich exhaust

I called the guy at the shop and he say's it all originates from the carb being bad. Thoughts?

sven914
12-21-09, 06:56 PM
It gave me a code:

23 intake air temp sensor out of range, low

45 oxygen sensor rich exhaust

I called the guy at the shop and he say's it all originates from the carb being bad. Thoughts?

The codes I posted in the reference thread are for a wide range of GM cars, so the 23 they have down is for the more common Mass Air Flow cars. The '80's brougham's not being MAF cars and still being carburetted, have code 23 as "Mixture Control Solenoid Circuit (signal voltage low)."

cadillac_jim
12-21-09, 07:07 PM
Okay, that clears it up. That one threw me off. Thanks.

cadillac_jim
12-21-09, 07:23 PM
What kind of mileage should I be expecting out of this car? I see the government website has them tanked at 16city 19combined 23highway. I would be ecstatic to see numbers close to these.

I called the guy that I got/inherited the car from, he said he was getting about 160-180 miles per tank......

sven914
12-21-09, 08:01 PM
I save up my gas recites and tally them up every year. I've gotten an annual fuel mileage average of 16 mpg for the last three years, and that includes idling the engine for fifteen minutes on cold days. A few times I've done a two week mileage (that's how long it takes to go through a tank) and have seen 19-22 mpg.

RocketFast321
12-21-09, 09:04 PM
I called the guy at the shop and he say's it all originates from the carb being bad. Thoughts?

:yup: Also i would replace the O2 anyways. It's only $20, and who knows the last time it was replace.

priscillabrougham
12-21-09, 09:18 PM
Once the carb is rebuilt, you should get about 16. I am getting about 15 out of mine, but I run at 70 MPH. My best was about 17, but that was before they upped the speed limit on the freeway I normally take from 55 to 70. Remember, those EPA estimates were put out when the national speed limit was 55.

I agree with rocketfast-change the O2 sensor as well. As a matter of fact, a faulty O2 sensor may be telling the carb to run rich. They might both be related. I'd still get the carb redone, but you may see an improvement once the sensor is changed.

Changing the O2 sensor is very easy to do when the engine's cold, takes about 10 minutes. It's on the passenger side rear. Be sure you buy the anti seize stuff to put on the threads.

Also, 307s are notorious for fouling EGR valves pretty quickly. I'm not trying to insult you at all, but attached is a picture of what you're looking for in case you haven't ever messed with one. It's on the drivers side of the manifold.

http://www.marcofrattarelli.com/photos/egr far.jpg

You could try changing this, and while the valve is off, cleaning the port up on the intake manifold real good with a brass wire brush (preferably-if it's a metal one, that's okay too, but be careful, as the manifold is aluminum).

cadillac_jim
12-21-09, 10:00 PM
Thanks for the picture, I know what an EGR is, but I had no idea where it was on this car. This is the first 307 I've had to toy with. Had an 88 Caprice, but I only paid $75 for it when I was in high school, basically I beat the _____ out of it, thing never did die.

RocketFast321
12-21-09, 11:16 PM
Also i forgot, could not hurt to replace the breather filter that's in the driver side valve cover. They are suppose to be white.

cadillac_jim
12-22-09, 05:13 PM
Ok, got the car back. It runs great, but isn't idling perfect. I called the guy he said he put the idle at 800, said he'd raise it to 850 and see if that would solve it. He also said it is probably built up with carbon since the carb has been dumping gas to the engine for so long. When at a stop it still slightly shakes, so hopefully he can get this figured out. The car is a lot more responsive and runs 100% better. Whoever worked on it before really had it hacked together. The mechanic noticed that the timing and idle had been messed with to compensate for the MC solenoid being broke/unplugged. I'll give an update on the MPG at a later date. Thanks everyone.

sven914
12-22-09, 06:04 PM
According to the emissions label the RPM's need to be at 1100 and the timing set to 20 degrees before top dead center, in park.

Also, to verify that what your guy is doing it right, ask him if he grounded out the ALDL or unplugged the distributor before he set the timing. Your car has computer advance timing, so the ECM must be taken out of the ignition system before you can set base timing.

cadillac_jim
12-23-09, 02:28 PM
So, It wasn't the carb or timing at all. It was cylinder 1 only getting 90psi, he said yesterday it was getting 120 and I believe him because it ran fine all the way home. I didn't notice the idle problem until later in the day. So he checked to make sure the wire/plug/cap were all delivering properly and they are. So his verdict is, carbon build up. And I'm going to agree with him on this too, noticed a lot of black sut in the snow today after I revved her a few time. Seafoam it is and we'll go from there.

He also said he wouldn't expect more than 14mpg....................... Wasn't a fan of that.

sven914
12-23-09, 02:57 PM
He also said he wouldn't expect more than 14mpg....................... Wasn't a fan of that.

Everyone is under the assumption that these cars are gas guzzlers, and they're always surprised to find out that they get mileage comparable to todays cars.

cadillac_jim
12-23-09, 07:58 PM
Well I'll find out what kind of MPG is get when I take it on a 1000+ road trip in a few weeks.

cadillac_jim
12-29-09, 12:57 AM
Been an interesting couple of days. I was getting ready to change all the belts and AC compressor, which are original, and the fuel pump just takes a huge dump on me. I've changed the fuel pump and it seems to run a lot better.

priscillabrougham
01-03-10, 07:53 PM
FYI-I just drove mine round trip from Dallas to Houston this weekend, and averaged 18.5 MPG at 65 MPH.

Ian6
02-24-10, 08:52 PM
yeah people are always surprised when they ask what mpg i get in my 307. 89 brougham. get an average of about 15-16 mpg mixed hwy and city. i've always wondered what mpg i'd get only driving on the hwy if i drive 60-65.