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1995 Oldsmobile Cutlass Supreme.. Mechanic has no idea sent it back to me!!

07-13-2004, 06:21 PM
Hi everyone. I have read every post on this site and nothing sounds like my problem really. I recently took my 1995 Oldsmobile cutlass to a mechanic for a serious problem. Let me tell you the specs: 1995 Olds Cutlass Supreme 3100 V6. Found antifreeze in the oil..Took to the garage.. They replaced the Intake Manifold gasket and sent it home.GREAT... Drove the car 60 miles a day for work 5 days a week. One month to the day my wife tells me the SES light came on. So I decided to drive it to work and let her drive the Grand Prix, On the way to my office the car ran rough and ide was really screwy. By screwy I mean up and down. But never died. So I pull into the officve lot put it in reverse and backed up shifted back to park and what I heard was very odd... Kinda a loud squeek the slight back fire She DIED. hasn't ran since. Had her towed to the garage. 4 days later I call they tell me they have no idea.. Olds dealer not having any idea on a product...anyhow I had it towed back home to my driveway. turned the key and here is what it did. Started ran for maybe 6 seconds but it was missing and backfiring badly then died. I cranked it for awhile never started agin maybe just a fire but backfired and died.. Cranks very hard I have checked the coils packs and replaced them they were ok. Plugs were all fouled it seemed so I replaced still no difference.I was thinking it was a timing issue so I wanted to post and see if anyone of you folks could help me. I am an averagve "backyard mechanic" I will take any advice given. Thanks. Firesuppressor. Just to add I do get fuel and spark .

07-13-2004, 10:39 PM
A couple things you need to check.

Check the spark plug wires and make sure they are not rubbing on the engine block. It is easy to spot spark plug wires grounding when you try to crank the engine at night (dark).

ICM (Ignition Control Module) uses the CKPS (Crankshaft Position Sensor) signal to adjust the timing. A lot of times the CKPS wire is rubbing against the engine block and shorting out the signal and not giving the ICM the reference signal and so sparks is not consistent. Probably the CKPS is bad. You can test the CKPS by checking its resistance (engine not started/cranked) and amperage (engine started/cranked).

Check for the proper Fuel Pressure using a Fuel Pressure Gauge.

Fuel Pressure Regulator has a diaphragm inside which is controlled by a vacuum via a vacuum hose. As the engine vacuum fluctuates, the vacuum pulling on the diaphragm changes and so the fuel pressure varies. However, if that diaphragm is ruptured then excess fuel is now being sucked out of the Fuel Pressure Regulator and into the intake manifold and causing the engine to flood and backfires and engine dies.

07-14-2004, 06:49 PM
also check your Trhottle Position Sensor mine was doing thing about 3 months ago i replaced it and have had problems sense

07-18-2004, 03:03 PM
Ok I have replaces the Fuel pressure regulator, Camshaft sensor, and Crankshaft sensor. I have cleaned the IAC and all throttle parts. still cranks very hard and backfires and will not start... Any more suggestions before it goes to the junk yard. I very much appericiate the comment in the past. Thanks

07-18-2004, 07:23 PM
On the way to my office the car ran rough and ide was really screwy. By screwy I mean up and down. But never died. So I pull into the officve lot put it in reverse and backed up shifted back to park and what I heard was very odd... Kinda a loud squeek the slight back fire She DIED. hasn't ran since.

You said that you heard a loud squeek? Is it more like a screaming banchee?

I've encountered that noise before on our 1987 Dodge Caravan V6 and the IDLE was rough and loud noise like a screaming banchee was coming from the engine bay. Tried to find the sound and it took me a couple of days on trying to find the source and finally found where the noise was coming from. The noise was coming from the connection between the exhaust manifold downpipe that connects to the exhaust pipe (before the catalytic converter and after the oxygen sensor).

Problem was that the catalytic converter was plugged up good and no way for the exhaust to come out except from that connection between the exhaust manifold downpipe and the exhaust pipe.

I confirmed it by removing the oxygen sensor and started the vehicle and it started right up and the IDLE was fine except for the very loud noise of exhaust coming out of the oxygen sensor hole.

Solution to the problem was a new replacement catalytic converter and the problem was solved.

You could have a faulty ICM (Ignition Control Module). The coil packs just sits on top of the ICM. Get a used ICM if want to at your local junkyard.

Another possibility would be a stretched timing chain and a worn out camshaft gear. Combine those two and your timing will be severely off and will cause the engine to backfire or not start at all since the timing is off.

07-18-2004, 07:51 PM
Before you give up you might want posting at at the Powertrain section.

One of the member posted some IDLE problem and engine flooding and backfiring. He was told that the problem was likely the ceramic resistor for the fuel pump. It explained that at a certain low RPM, the ceramic resistor is used but when it reaches a higher RPM then it by-passes ceramic resistor and it operates the fuel pump at high pressure. When the ceramic resistor fails then the fuel pump operates at the highest pressure eve though the it has not reached the required RPM and the result is a flooded engine all the time. I'm still not sure if that ceramic resistor for the fuel pump is on all Oldsmobile or GM vehicles or just specific vehicle.

08-07-2004, 11:09 AM
from what you are saying about all the plugs being fouled and coolant in the oil, it sounds to me like you have a busted head gasket...

10-12-2004, 12:51 PM
I have a '95 cutlass on my lift. The engine has a clunking noise when you rev the engine not under load. I found (by turning the crank with belt off) that there is severe chain slap in the timing chain.

Don't know if this will help but a bad timing chain and gears can cause misfire and running problems.

Good Luck.

12-18-2004, 03:15 AM
i think jnoinky is right, i've never had this happen but have seen and heard the results. messing with the sensors is likely going to be a waste of time. I can't think of any that would let coolant into the oil. there may be however but I doubt it.
Also your mechanic may have done a junk job of putting your intake back together, or maybe just got in a hurry and forgot to torque a couple bolts.

12-19-2004, 11:53 PM
One month to the day my wife tells me the SES light came on.
Did you scan for codes???

12-22-2004, 04:22 PM
Check your MAF, bethca it runs after new one and never threw a code.

01-02-2005, 11:58 AM
on the 3.1 liters the intake and the heads often have to be milled when replacing gaskets. I just did a 97 3.1, heads warped 6 thousands, and the intake 7 thousands. Can't just replace a gasket anymore.

01-03-2005, 07:35 PM
I have a cutlass with a 3.1 liter V6 and It did the same thing I scaned the computer for codes and there was no codes it was the fuel pump. to replace the fuel pump you have to drop the tank to pull the old one cost me $150 for one from the wreckers and I got it installed for free.

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