: Intake Manifold Removal, '97 SLS



cshupe
04-21-09, 01:40 PM
I am in the process of removing the intake manifold on this '97 4.6 NS for a starter install. Book says the manifold gasket can be reused...good idea?
Will I need to remove the injectors/rail from the manifold to get the manifold off the engine? I'd like to leave them in if possible, I think I can get the fuel rail lines out while attached. Ideas?
Why put a starter under the intake manifold, anyway??!

Ranger
04-21-09, 04:26 PM
No reason why you can't reuse the gasket if it's in good condition.

I think if you separate the fuel line you can leave the fuel rail on the manifold.

One reason the starter was put there I think is because of space. The added benefit is that it stays cooler than tucked under the exhaust manifold as well as cleaner and drier.

tateos
04-21-09, 04:44 PM
I replaced my intake manifold gaskets when I did my HG project. My thoughts are: Why not? They are not expensive, and do you want to possibly do the job over again? Yes, you can just disconnect the two fuel lines and remove the manifold and fuel rail as one assembly.

I don't think I have heard of a Northstar starter failing - they are pretty bulletproof. I hope that solves your problem.

RM

cshupe
04-21-09, 05:38 PM
Thanks for the replies.
The local AZ wants over $80 for the gaskets, but RockAuto is about $30...I just don't want to wait a couple of days for shipping. My son needs his car running!
I'll take the manifold off tonite and try to save the gaskets...but if they come off bad or tear, he'll be waiting a while longer.
Indications are that the starter is bad, altho he has had steering column wiring issues. The solenoid clicks once when you twist the key. AAA professional jump start couldn't turn it over. Before he got stuck, he got a new battery, and it did start for a couple of days. It's been turning over slower and slower for a while now, and this last heat wave seems to have finished the battery and starter off.
I can't imagine a worse location for the starter in terms of maintenance. I'm sure it's a space limitation due to the transverse engine/transmission location, but wow! I go along with the guy with the '66 Mustang; 30 minutes, including jacking up the car. My '66 was like that!

tateos
04-21-09, 05:55 PM
Sure - you can try to re-use them - the factory say to, but they are 12 years old!

They will not fall apart or tear - they are something like a silicone runner on a plastic carrier - you'll see when you get it off.

Where are you? We are getting a heat wave here in Phoenix - over 100 today!

Ranger
04-21-09, 07:11 PM
Look closely at the cables and make sure there is no corrosion on or in them.

cshupe
04-21-09, 07:26 PM
I'm in Palm Desert, CA, and it's 103 here today, 102 yesterday...cooling to 96 by Friday! We had a hot weekend. He tells me his car does not like the heat. He just relocated here from San Diego, where the SLS was born, and where it was much happier..
Good point about the age of the gaskets. If I had known about having to remove the intake manifold to get to the starter a bit earlier (imagine my surprise last nite, arriving home with the starter and just cracking the manual regarding r&r...!), I would have gotten a set ready to go.

cshupe
04-21-09, 07:28 PM
I will give all the electrical connections a good look, and probably some contact cleaner and some a wire brush too. Never hurts...and the stuff under the manifold gets the closest exam.

cshupe
04-21-09, 07:33 PM
Let's say the manifold gaskets come up alright...would you use any kind of adhesive or sealant on them? One side or both sides? What do you do with new gaskets? What can I expect regarding adhesives on the original factory gaskets?

Ranger
04-21-09, 07:37 PM
No adhesive or sealant.

Krashed989
04-21-09, 09:34 PM
The intake manifold looks harder than it is.
-Remove the beauty cover
-Remove the bracket carrying the throttle and cruise control cables
-Unplug necessary wires, coolant hose (for the throttle body heater), and vacuum lines
-Disconnect fuel lines
-Remove the eight 10mm bolts holding it down.
-Lift the manifold off of the engine (The gasket is clipped onto the manifold)
-The starter bolts are 10mm.
-Always test the new starter before installing it

cshupe
04-22-09, 02:18 PM
Well yes, the intake manifold removal is easier than it looks.
Once I had the right tools (fuel line disconnects), it came apart in about an hour.
I was shocked to see that the positive cable to the starter had become unbolted! There was evidence of arcing on the copper, and I found the loose nut under the starter. I decided to install the rebuilt starter anyway, as long as I was in there...
After cleaning the intake port flanges on the heads (nicely machined surfaces in there) and a good look at the injectors/ports/gaskets, I decided to reuse the manifold gaskets which looked okay, if a bit flat (crushed?) without a lot of rise in the port o-rings. There had been no adhesives used, I didn't use any upon reinstallation, and the manifold lifted right up on disassembly.
It all went back together very well and pretty straightforward. No parts left over either, which is a good thing.
Started right back up and runs well. Except....
The idle is way too high, about 1500rpm or so. Really hard on the transmission on shifting from park to drive. Given that the PCM was without power for two days, I think it needs to relearn. Reading the codes from the dash (good trick there!), I got three Powertrain codes: P0122 - Throttle Position Sensor Circuit Low Voltage; P0603 - Control Module Long Term Memory Reset; and P1122 - Throttle Position Sensor Circuit Intermittent Low Voltage.
I am going to check for vacuum leaks asap, with carb cleaner around the base of the manifold and all the hoses on top. There doesn't seem to be any way to adjust the idle speed...and I'm pretty sure the throttle cable went back on right. Do these codes indicate a defective TPS? I sprayed all the connectors with contact cleaner before reassembly.
Any other ideas here? Think I need to get some new manifold gaskets and stick them in now? I found a Fel-Pro set at Napa for $50 that will do. The kid was happy to have his car back, but I need to get it running right...
Thanks for any help!

cshupe
04-22-09, 02:23 PM
One other point here: the book I had indicated 80 inch pounds torque on the manifold bolts. That's about 7 foot pounds of torque, and neither of my torque wrenches go that low, so I am sure the manifold is not torqued perfectly. The Haynes manual also didn't have a proper diagram for torque sequence for this model (is the factory manual available anywhere online?), so I started in the center and worked my way to the outside while crossing over...I won't be too surprised to find a vac leak at the base of the manifold. Where do I get a torque wrench that goes that low??

Submariner409
04-22-09, 04:11 PM
For light torque work such as the manifold, get a small click torque wrench which sets to inch pounds vs ft. pounds. Try Craftsman or SnapOn. Maybe a NAPA dealer. You might also be able to find a light duty beam torque wrench calibrated from 0 - 20 ft/lb.

Your torque sequence is basically correct - from the middle two bolts crisscross out.

Instead of spending the $135 for a real Helm GM Factory Service Manual you could either shop eBay or subscribe the car for 1 or 3 years to www.alldatadiy.com

Check the cable attachment to the throttle arm. Also check the TPS connector. Last resort, throttlebody cleaner, toothbrush, rags. (Prop the butterfly open and scrub away. Don't get much cleaner 'way past the butterfly.)

cshupe
04-22-09, 06:14 PM
Do you think I would get a code for a vac leak?
I did have the manifold and throttle body upside down for an hour or so...could it affect the tps?
I didn't care for the manner the throttle cable snaps into the cam on the TB...but it seemed to be in the correct position.

Ranger
04-22-09, 06:44 PM
You can only get a code for an electronically monitored device. So no, you won't see one for a vacuum leak. Likewise, having the TPS upside down for a while won't affect anything. Release the cable, and if the throttle lever closes more, then the cable is holding the throttle plate open. If not, look for a vacuum leak.

cshupe
04-22-09, 07:24 PM
Makes sense.
I will look at it more tonite.
Attached is a pic of the nutless battery cable. The nut was under the starter!

cshupe
04-22-09, 11:48 PM
I put the pic in my album....don't know why it doesn't display here.

Submariner409
04-23-09, 01:03 PM
............it's there.................:rolleyes:

Krashed989
04-24-09, 03:22 AM
Spray some carb cleaner around the intake near the powersteering pump. There's a backfire valve there that gets all dirty and grungy. Then, if you mess with it, it might not seat right which would cause a vacuum leak.

cshupe
04-27-09, 01:13 PM
He tells me now that the idle has calmed down and the car is running well. I haven't been able to see it again yet; I was going to spray carb cleaner at the base of the manifold. I didn't know about the backfire valve, but it will get some attention next chance. Maybe it did seat itself, or the computer relearned...he did say the check engine light went out after a couple of days. Good sign.
Thanks for all the help. The project appeared daunting to begin with, but with some input turned out to be easier and more successful than I anticipated!

32vmonte
04-27-09, 10:50 PM
Spray some carb cleaner around the intake near the powersteering pump. There's a backfire valve there that gets all dirty and grungy. Then, if you mess with it, it might not seat right which would cause a vacuum leak.


I was wondering what that little door was. I discovered it last night as a matter of fact. I was like WTF is that :confused:. I noticed the rubber seal around it was just hanging off and there was blow by residue I guess all around the hole and on the back side of my power steering pump. Guess I know why it idled at like 1300-1400 before the HG went.



He tells me now that the idle has calmed down and the car is running well. I haven't been able to see it again yet; I was going to spray carb cleaner at the base of the manifold. I didn't know about the backfire valve, but it will get some attention next chance. Maybe it did seat itself, or the computer relearned...he did say the check engine light went out after a couple of days. Good sign.
Thanks for all the help. The project appeared daunting to begin with, but with some input turned out to be easier and more successful than I anticipated!


I believe I would rather change the the N* starter than on my 3.1 Monte motor anyday.

Rodney_98
09-03-09, 08:54 AM
Thanks for posting images of the starter location!
I will be replacing the starter on my '98 soon due to intermittent clicking when I try and start the engine.
I've done all of the obvious, cleaned the battery terminals and the battery has been replaced.
It sounds to me like a flat spot on the armature and when the engine is warm the starter is much slower turning the engine over.
One thing I will do as suggested in the service manual is to clean all of the fuel and other connections and the top of the engine well before dis-assembly.
I have already gunked the engine off and will now use compressed air and carefully blow the fittings clean of any debris.
Oh what fun! I'd guess the start problem is one reason the car was so inexpensive when I bought it.
The cost of the rebuilt starter was 118.98 exchange with a life time warranty.
GM wanted over 300 for a rebuilt one.
I found some on Ebay for around 80.00 including freight {made in China} but only a year warranty and if it failed the hassle of trying to get a replacement.
My local parts store got my money.

Submariner409
09-03-09, 09:25 AM
If there's not a core return on your old starter, take it to a local automotive electrical shop and have them rebuild it. Not expensive and good as new. Same for alternators.

You may find that the positive starter cable is loose or has a corroded connector lug.

Don't panic if you find water in the valley (from your cleaning job) - and I'll go on record as saying that a Gunk job on a FWD Northstar is not a good idea.

Rodney_98
09-03-09, 10:02 AM
The core is 20 $
I was careful to not get any of the electric components wet and was aware of the damage that could be done with the water.
I blew the water from the engine after the cleaning.. the cleaning was focused on the lower block inspecting for oil and coolant leaks.
A little common sense is always exercised when working on these or any machines.
Thanks for the advice.

ponyboyt
09-03-09, 10:31 AM
Starter in my 97 was new (300,000 km's) so i took it since it was an easy swap with the wiring harness. I needed the knock sensor and it was wound in with the starter cables. I had already ordered new intake gaskets, $60 shipped from M&A local parts store so i ordered em. Now that i have new and old gaskets side by side and can see the difference.... i am glad i ordered them. The new ones, they are hard gaskets but the square inner ring that goes on the ports themselves is a soft rubber. The new ones are MYCH softer than the originals, and they have a bit of a raised lip in the center. Not so much lip on the old ones. I compared them to the 4 used gaskets i have now (2 engines) and yep... im glad i bought new. I can probably get away with reusing the old, but they are here and paid for so ill use them.

Rodney_98
09-03-09, 11:06 AM
It would be crazy to NOT replace the gaskets once the intake was removed IMO.
intake leaks = lean condition = burnt intake valves.

Rodney_98
09-03-09, 03:33 PM
Well that was easy!
took less that 2 hours and had to run to the parts store for some blue loc- tite
When I removed the intake bolts they were very loose.
intake gaskets were $41.98 from the parts store.
all looked good other than a mouse nest in the valley area.
The new starter spins the engine over much faster.
Good Deal!

Submariner409
09-03-09, 03:59 PM
Careful..............the torque on those bolts is only about 7 ft/lb . Too tight and you crack the bolt bosses.

Rodney_98
09-03-09, 05:20 PM
yep all torqued to 89 lbs / inch.
I would be more concerned with breaking and displacing the intake gasket o-ring seals.
all of those parts look to be delicate and fragile.
I saw no reason to remove the throttle cables ect. simply swung the manifold to the drivers side of the engine compartment and had it rest on a cushion while doing the other work.
The engine runs much better. I'd guess the gaskets were leaking some.
its all good so far. :)
Thanks

ponyboyt
09-04-09, 09:29 AM
all looked good other than a mouse nest in the valley area.


I found one of those in my donor! That and a spare starter bolt.... i'm really starting to doubt the dealer mechanics'.....

Rodney_98
09-04-09, 10:24 AM
At least it wasn't found in the oil pan ;)
I find spare parts quite often when working on cars and trucks @ the body shop, in doors and under the trunk liner and carpets..
Older autos seemed to be worse for that kind of thing happening from the factory.