Cadillac Owners Forum banner
  • BEWARE OF SCAMMERS. Anyone trying to get your money should be checked out BEFORE you send anything anywhere.

'83 Eldorado problems with a 4.1L engine

16K views 35 replies 10 participants last post by  ELDORADO2K  
#1 ·
hi ! , i am the proud owner of several rare cadillacs in France , but 1 of them , a 83' eldorado causes me some troubles : she only has 23 000 kms on Odo, i can quite certify to be true . Problem is , when cold , engine starts and drives as it should : low gas consumption , smooth and power . After a drive , whatever the distance , and when re-starting ( engine hot ) it starts and stops and again and again with a black smoke coming out the exhausts !. First time it happened , it did it a couple of times , but now , it does it 30 to 50 times before , suddently , running again perfectly without having done anything !. This is a non sens problem and my mechanic does not find any solution to solve it ! We already changed everything , including injectors , all candles , wires , sensors ( oxygen and temperature ) fuel pump and filters , all parts new , of course . No oil leakage , we really don't know where to look for ! default codes are 11, 15, 21 , 28 and can't be erase when using normal procedure . thank you in advance for your help and sorry for my english !
 

Attachments

#2 ·
Hi Freddy and Welcome to the forum. Not to worry, your English is better than some of the other posts we get.

Considering your codes: First, do you have the OEM Service Manual? Might be an important addition to get for diagnostic use. By review of the codes you listed, I don't see any code 11 listed in my manual. The code 15 is the coolant sensor which might be the issue. The TPS is wired in with the coolant sensor and when the engine is hot a bad signal from it will screw up the fuel input signals to the computer. Had this problem on my '83 Seville. The code 21 is the TPS which is also a fuel regulator and the combination of the 15 and 21 prompts me to believe the coolant sensor is bad. However, you might want to check the EGR and the Catalytic converter for clogging issues, either or both can contribute to the black smoke issue. I assume you have done a compression test and I would pull some "candles" (spark plugs) when the black smoke is happening to check for a fuel issue.

There are some more knowledgeable guys than me on here who will probably chime in to either correct or supplement my comments so hang in there. We love there old boats and are to help as much as possible.
 
#3 ·
To clear the codes hold the OFF and HI buttons on the heat and A/C controls. You will see 0.0 and then 7.0. Shut the ignition off for at least 10 seconds.

You really need the factory service manual. It sounds like a condition where the engine is being flooded with gas. My first thought was a leaking injector but you said that was changed.

There is an emissions related valve in the exhaust down pipe on the passenger side. You can kind of see it from above but better from the bottom. It closes on a cold start. When warm it opens. The default position should be open.

Code 28 is a transmission 4th gear pressure switch issue. Possibly change the transmission fluid and filter and that may fix that.

The coolant sensor is near where the upper radiator hose attaches to the thermostat housing. Was that one changed?
 
#5 ·
Salut! Pretty car. I can't give you much help Freddy. But here's the list of codes if you don't have it. https://www.autozone.com/znetrgs/re...pair_guide_content/en_us/images/0900c152/80/1c/85/85/large/0900c152801c8585.gif

EGR valve is an interesting idea. I just replaced mine after I failed my emissions test. To inspect it I had to remove it, which is difficult because the bolt is difficult to reach. EGR can be cleaned, but mine had failed rubber and didn't hold vacuum.

Here's the OEM/official Service Manual they are talking about, $40 shipped to France, I think: 1983 Cadillac Service Information Shop Manual Commercial Chassis & Limousine | eBay
 
#6 ·
Salut! Pretty car. I can't give you much help Freddy. But here's the list of codes if you don't have it. https://www.autozone.com/znetrgs/re...pair_guide_content/en_us/images/0900c152/80/1c/85/85/large/0900c152801c8585.gif

EGR valve is an interesting idea. I just replaced mine after I failed my emissions test. To inspect it I had to remove it, which is difficult because the bolt is difficult to reach. EGR can be cleaned, but mine had failed rubber and didn't hold vacuum.

Here's the OEM/official Service Manual they are talking about, $40 shipped to France, I think: 1983 Cadillac Service Information Shop Manual Commercial Chassis & Limousine | eBay
hi all gyes !
first of all , plenty of thanks for taking my problem under consideration and your help ! sure , i will not have to waste the engine !
code defaults : please read 13 instead of 11 !
i do have HAYNES MANUAL , for this car , nothing else !
i transfer all your ideas to my mechanic and come back to all of you with results
attached 3 of my other babies !
 

Attachments

#8 ·
I had the same problem last year. I’d take a look at that MAP sensor(manifold absolute pressure sensor) if there’s black smoke I’d take a look at that. If you do a code test it will most likely pull up the code for your Idle sensor control unit malfunctioning but I think it’s the MAP sensor issue personally. If and after you replace your gonna have to Accelerate to the floor on the bastard and clean out all the smoke and crap from the engine and give her a nice oil change cuz that oils gonna be nasty. You will see a difference
 
#9 ·
13 is the oxygen sensor code.
Two wire sensor is GM part 5613719 Use a sealer (anti-seize compound) such as a high temperature compatible with O2 sensors.

MAP sensor is part number 16006832. Located in the dash behind the glove box I believe. Ebay sellers have photos. Makes me wonder if the vacumn hose is not connected or has a leak.
 
#12 ·
13 is the oxygen sensor code.
Two wire sensor is GM part 5613719 Use a sealer (anti-seize compound) such as a high temperature compatible with O2 sensors.

MAP sensor is part number 16006832. Located in the dash behind the glove box I believe. Ebay sellers have photos. Makes me wonder if the vacumn hose is not connected or has a leak.
hi ! thank you for your help ! I was wondering for a while about depression but my mechanic certify that there nothing to see with the problem .
i will order the MAP -(by Rockauto , I suppose , or do you have a better supplier to recommend ? ) and thank you for localisation : i believed to find it onto the manifold , not behond the glove box ! best regards ......
 
#11 ·
hi dear , ! both cars are 79' with the 350 Olds in . They were totally renewed , frame off , rotissery , and all defected parts changes with new ones .
For sure , paint job is also new , just engine and gearbox are matching numbers .
there are 4 Stretch Eldorado's i know in all Europe , and i own 2 . A marron one is in Germany , coming from an english car museum , and the last is a 84' white one in spain , actually for sale but very badly restored !
every where i go in France or else people stops me for taking pictures ! it's incredible to realize how beloved are these american glory witnesses !
having owned also a 81' with the 8-6-4 engine , i pretend 79' to be the best year for collectable !
don't you ?
regards
frederic
 

Attachments

#15 ·
i was just thinking about performances , and driving experience ! having had the 3 motorisations , definitively , the 350Ci Olds was the best : powerfull , silence , smooth and silence , just what we are looking for when buying a Cadillac !
design is only a personal opinion , front grill in 79' was mostly made of higher quality than 82 and later years ! wire wheels can be installed on every year and will not change the value in less of the car because "non matching" .
talking about engines , i never heard bad reports about the 350 Olds , and at contrary , many complains against the 368 and later the 250 CI !
in a world , i love all my car , being 350 or 250 ci , they all procure lot of fun driving them on our small country roads ...

all the best for you and all of yours
frederic !
 
#19 ·
i was just thinking about performances , and driving experience ! having had the 3 motorisations , definitively , the 350Ci Olds was the best : powerfull , silence , smooth and silence , just what we are looking for when buying a Cadillac !
design is only a personal opinion , front grill in 79' was mostly made of higher quality than 82 and later years ! wire wheels can be installed on every year and will not change the value in less of the car because "non matching" .
talking about engines , i never heard bad reports about the 350 Olds , and at contrary , many complains against the 368 and later the 250 CI !
in a world , i love all my car , being 350 or 250 ci , they all procure lot of fun driving them on our small country roads ...

all the best for you and all of yours
frederic !
Yea you’re right, the wheels & hubcaps can be interchanged.. But realistically how often does that happen? I’ve never seen a 79’ Eldorado with 82’ hubcaps.[emoji4] And we’ll just have our own preferences regarding the grills.

As far as the engines, maybe I’ve got a soft spot for the HT 4100 since it never let me down during the time I owned it. I even drove that car to Mexico once. It ran like a champ. Lol.

what do you think about these wheels ? funny , isn't it !
Those wheels look good from the side view, and don’t get me wrong, I’m not saying they look bad, but it’s just that they remind me a bit of a genre of customized cars they call Donk. Those wheels look borderline donk. But at the same time they’re befitting of such an extravagant vehicle.

Here’s a couple of pictures of Donked out Cadillacs.

Image


Image




Those wire rims appear to be Appliance rims. If I'm not mistaken about a $4K dealer option.
Wow that sure was expensive for that day... I have recently learned about them being Appliance wheels.. But for the longest time I somehow thought they might’ve been made by Vogue, even though I’m pretty sure Vogue doesn’t even make wheels, right?

The reason I thought that was because the design on the center cap sort of resembles the Vogue emblem. I also pictured them being a perfect match with Vogue tires when the car was brand new. Similar to how later model Eldorados with Vogues sometimes seemed to come with special wheels that always looked great.

may be more as there are 6 real rims , not 4 ! This car was transformed by American car coachworks in California . The 2nd was by COOLIDGE Motors cars in Fort Lauderdale , early in 79 , just before the company stopped its activity .
From what I understand, those custom extended body Eldorados were said to be “hand made” cars.

I saw 1 for sale online a few months ago. It was brown just like yours.. I forgot what the asking price was but they were asking quite a bit.
 
#25 ·
Salut. I am not 100% sure. But it's the same exact part for 1982 to 1985. So I would bet money yes.

I think your priority should be solving the trouble codes. And like people said before, you need the official Cadillac 1983 Service Manual. C'est un must.
GOOD MORNING TO ALL OF YOU !
thank you to all of you for your good informations ! everything is clear now , and all troubles codes desappeared ..
let me tell you the end of this story : after receiving and installing all new spare parts you recommended including the MAP Sensor , all troubles were off , excepted 1 new : 026 ! we changed the motor (iddle i suppose ) but default remained ! the engine started well , running well no trembling , but suddently stopped . restarting , and again 2 or 3 minutes later , stopped again : the reason was lack of vacuum , but why , after 3 minutes good running ... and right vacuum ? 3 complete days looking for the source later , the mechanic pulled out the main connector between the engine case , and the cabin : some pins were out , as somebody by the past desinstalled it for an unknown reason , and badly reconnected it ! so , by cold temperatures , some connection were ok , but disconnected when hot : bad contact . my mechanic repaired all of them , and now all is 100% Ok , no more default codes , engines is now running strong and smoothly as a Cadillac should !
don' t forget , the car as only 24 000 km ( 16 000 miles ) on the odometer !
thanks again , and when 1 of you come to France in the area of Dijon (worldwide known mustard !) i will be happy to welcome him and show my small collection and share our passion !
thanks again
frederic
 

Attachments

#26 ·
Hi Freddy, all three of your cars are very nice. Maybe you have room for one more Custom '83? This one is two tone red and has a roof line similar to your white one. I thought that the colour combination is very attractive. I do not know about this car but thought it might interest you given the cars you have already. Enjoy. Dave

 
#27 ·
Hi dears , i was just having a look on a Cadillac Allante from 87' , and was poiting out that its engine ( 4.1L ) was developped to produce 170 hp ! do you have any idea of what to change or modify in hte engine in order to get this power ?? My car is running fast now , with quite a very low gas consumption ( more than 20 miles/ gal at 65 m/h ) but more power would be more funny !
about the Eldorado for sale by KIJIJI , i saw the ad by the past , and , as i already 2 of themĂą , i can't buy a third one !
BUT , i am always looking for buying rare and funny cars , specially when built less than 500 pieces .
in this way , i bought 4 and 5 years ago , 2x 79' Trans Am convertible , conversion made by NCE in California : these cars are tipically what i love for my collection !
attached , pictures of them !
god bless you all !
 

Attachments

#28 ·
i was just having a look on a Cadillac Allante from 87' , and it was pointed out that its engine ( 4.1L ) was developed to produce 170 hp! do you have any idea of what to change or modify in the engine in order to get this power ??
WOW! 170hp from a 4.1??? Had to be some extraordinary modifications to do that. If possible, provide us with any particulars, especially who, what, where we can contact the person(s) who accomplished this. Where did you find this Allante, any site info would be really helpful.

Sub... Is this really feasible... Please comment!!!
 
#29 ·
hi , it seems to be the regular engine installed in the Allante from 1986 to 88. there is same power increasing with the 4.5L upgraded to 200 hp !
you can get confirmation by reading infos at your next CADILLAC dealer !
in this forum , you'll get same information :Boosting HT4100 Performance
BOOSTING 4.1L PERFORMANCE ..
it's seems to be too nice to be true , but , why not !
any comment will be highly apreciated !
 
#30 ·
Just a quick update.... Check out "ultimateSPECS.com" for more info. The 1986-1988 Allante 4.1 engine was the LC7 version of the standard 4.1 and rated at 170 HP. This was NOT the 4.1 we have in our longitudinal '80-'85 Sevilles/Eldo's, this was the transverse production model. Apparently there were some custom upgrades made to the standard 4.1 block/etc to get this much HP out of it.... 16valves, roller cam, and more. Certainly burst my bubble hoping for some alternative to the wimp i have.

I'm still dreaming of a suitable replacement for the longitudinal 4.1 in my Seville, but without $80-$90K to convert to a 350 chevy and rear wheel drive, I'm stuck puttering along with a great looking car but getting passed by the Isetta"s, Yugo's and 35HP Volkswagen busses still on the road. Oh Well, she still has her looks if nothing else.
 
#31 ·
HA HA , too nice to be true ! do you believe in that info from DrDave in this forum : just changing the cat converter ..... it can rob the car of 30-40 precious horsepower as well as throttle response ...?
79' models : i actually own 2 of them , they are powered with the 350 OLDS , front wheel drive . I would believe that installing this engine instead of the HT4100 might be quite easy ...?
but , in term of consumption , you will see it climbing to the summit , twice or more than with the actual 4100 . The right middle solution would remains in some easy developments such as a more efficient coil , sparks plugs , and , why not , a magnaflow cat muffler , isn't it ?
i am not a mechanic at all , just pay the bill , and drive the car !
all points of view will be much apreciated
 
#32 ·
hey are powered with the 350 OLDS , front wheel drive . I would believe that installing this engine instead of the HT4100 might be quite easy ...?
Yes, the Olds is the preferred replacement for the 4.1, BUT, and this is a big BUT; finding a low mileage Olds 350 is improbable if not impossible. Cadillac screwed the pooch by rushing the 4.1 into production to adhere to the Gov. mandate during the oil debacle back when the Olds 350 and Chevy 350 were available. I'm not sure of the mindset during this time period, as they were slipping Chevy 350's into Caddies unbeknownst to the Caddy buyers who became generally pissed to find a Chevy engine in their cars. Corporate Moguls are generally idiots as they have proved with all of the stupid electronic crap in their current cars, but I guess it is to force you to return to the the Stealership for diagnosis and repair. As far as replacing the 4.1 is concerned, there are no acceptable bolt in replacements that make any financial sense. Cost wise, you buy a motor and spend $$$ rebuilding it, then more $$$ adapting it to the current electrical configuration which may or not work. If you have a 4.1 now, just have it rebuilt: sure, you can have it bored and resleeved to the 4.5 tolerances and upgrade the cam, etc., if you want more oomph. But have it done by someone you trust, these "rebuilders" advertising their wares are buying junk motors out of a recycling yard and who knows what condition they are in. There is a reason it was in the junk yard; generally because of the failing characteristics of the 4.1 (or other) and an engine with high mileage that is not "remanufactured" but "rebuilt" is going to cost you plenty later on.

The 4.1 is a reliable engine, contrary to common belief, generally because of the lack of following the OEM maintenance necessary to keep it going. Alright, the gasket slippage from mating iron heads on an aluminum block was common, but the new improved gaskets installed during a rework seems to have been effective. And not using the "ginger" additive to the radiator has been the owners fault when leakage occurs. For me, I love my Seville and instead of shelling out $40-$50K for a new plastic junk box, I'll spend $7K on rebuilding what I have. I enjoy getting the compliments from strangers on how nice "Christine" looks, which justifies the need for spending time under the hood keeping her running properly. Oh, and as a side note: I seriously doubt a clogged Cat can rob "30-40" HP, my experience when mine failed, it just would not run and the heat generated from it set my rug on fire. Losing that much HP there would not be enough left to even move the car, much less drive it. But that analogy is interpretive.
 
#33 ·
The Allante has port injection-unfortunately nothing can be done to a longitudinal 4100 to increase power besides swapping the liners pistons and fuel injectors to 4.5 units.

The engine was tuned to retain a similar driving experience to the 6 liter with much better mileage. Horsepower remained basically the same, and the drop in torque was supposed to be masked by the much quicker axle ratio.