Stalling when warm.

[mpalazzo]

Hello!

 

I have a 1988 Reatta and I'm having trouble with the car stalling. When engine is cold, it runs and drives perfect with no issues. if I try to start at operating temps the car will idle poor at 5-600 rpms. it will stall when attempting to drive it, but if I hit the gas hard it will jerk and take off. After that, it will run perfect with no issues. The car has no trouble codes showing in crt.

 

I just did the intake manifold gaskets and cleaned everything associated with it. throttle body is clean, new MAF sensor, new spark plugs, wires, and coil pack with new ICM. The oxygen sensor is new as well. I am stumped on what could be causing this other then the crank position sensor, but I do not want to dump my whole wallet into this car, its my summer cruiser I just bought 6 months ago. Anyone have any ideas on what this could be or have any diagnosing help?? I would greatly appreciate it.

[Frogware]

Hello!

 

I have a 1988 Reatta and I'm having trouble with the car stalling. When engine is cold, it runs and drives perfect with no issues. if I try to start at operating temps the car will idle poor at 5-600 rpms. it will stall when attempting to drive it, but if I hit the gas hard it will jerk and take off. After that, it will run perfect with no issues. The car has no trouble codes showing in crt.

 

I just did the intake manifold gaskets and cleaned everything associated with it. throttle body is clean, new MAF sensor, new spark plugs, wires, and coil pack with new ICM. The oxygen sensor is new as well. I am stumped on what could be causing this other then the crank position sensor, but I do not want to dump my whole wallet into this car, its my summer cruiser I just bought 6 months ago. Anyone have any ideas on what this could be or have any diagnosing help?? I would greatly appreciate it.

 

Hello & welcome to the forum!

 

I was doing some digging on the same issue a while back and did almost the same stuff to mine (minus the manifold and O2 sensor) but still had the problem, but not to your extreme. Mine would only die every so often and before that I was having acceleration issues but the new ICM fixed that.

There were only a few more things left to do before I decided to look at the Cam Sensor;

 

First, clean the EGR

 

Second, replace the fuel filter

 

Third, rebuild/replace fuel injectors

 

Well last week I did the EGR and from startup it reacted very well and is idling much better. It is very responsive, although I have only been driving it for a couple days and have yet to see if that was the culprit, Fingers crossed.

 

You might want to try those things I have listed above if you haven't already Good Luck!

 

Edit:

Thanks Ronnie, I forgot about the IAC that is also on my list to check.

[Ronnie]

Welcome to the forum! Have you checked for codes using these instructions? Have you tried cleaning the Idle Air Controller (IAC)? IAC Cleaning Instructions

[mpalazzo]

Thanks For the input! I cleaned the IAC and all of the components to the throttle body when I did the intake gasket. I just took out the IAC and cleaned it a second time (still was a little grungy). The car is still idleing poor, and I did check the crt codes via climate controls. when I override the IAC valve, the numbers showing while its idling is all over the place, and If I take control of it, I can fix the poor idle by adjusting it just a small amount. Also, I have changed the fuel filter already. All of the injectors have been cleaned with new orings. The EGR has new gaskets, and I attempted to clean it when I did the intake gasket, it had bad carbon buildup.

[Ronnie]

If the IAC reading is all over the place the ECM may commanding it to do that in an effort to get the idle in the correct range. A likely cause for that is a vacuum leak somewhere. What happens if you keep your foot on the accelerator to keep the idle at 1000 RPM? Does the idle still fluctuate or does it idle steady at 1000?

[mpalazzo]

When I hit the pedal it will have a steady rpm

[Ronnie]

When I hit the pedal it will have a steady rpm

 

That's because you are overriding the IAC. If I were you I would start here and see if you find anything wrong.  Vacuum Line Inspection

Did this idle problem start when you changed the intake gaskets?

[Ronnie]

If the vacuum lines look good try unplugging the O2 sensor and see if the the idle problem goes away. Unplugging the O2 sensor will keep the ECM from going into closed loop operation when the engine warms up. The ECM will set a code but you can clear it later.

[mpalazzo]

The problem was there before I did the gasket. It got worse after I did the gasket, which I replaced it because oil pooled on Top of manifold. I replaced all of those vaccume lines the only one that could possibly be a concern is the gasket between the manifold and the four way line coming out of it. It was very brittle I reused it because I was not able to find a replacement. I'll check that gasket any suggestions of what to use to make a new one?

[AZ Ron]

You can rent a noid light to test that your injectors are firing.  Most auto parts stores have them and can tell you how to do this.

Good luck mate!

[retired mechanic74]

The problem was there before I did the gasket. It got worse after I did the gasket, which I replaced it because oil pooled on Top of manifold. I replaced all of those vaccume lines the only one that could possibly be a concern is the gasket between the manifold and the four way line coming out of it. It was very brittle I reused it because I was not able to find a replacement. I'll check that gasket any suggestions of what to use to make a new one?

 

.....It's showing the classic signs of a vacuum leak. Suggestion, Run the engine till it goes into closed loop, remove the rubber tube that runs from the t. body to the filter housing and with the engine running gently cover the air intake of the throttle body with the palm of your hand and see if the engine smoothens out , if it does you have a vac leak. Next using carb cleaner spray around t. body, intake gaskets and any other place that would have vacuum (Be light with the carb cleaner) if there is a leak the rpms will increase and that is where the repair would be needed.

[retired mechanic74]

 

.....It's showing the classic signs of a vacuum leak. Suggestion, Run the engine till it goes into closed loop, remove the rubber tube that runs from the t. body to the filter housing and with the engine running gently cover the air intake of the throttle body with the palm of your hand and see if the engine smoothens out , if it does you have a vac leak. Next using carb cleaner spray around t. body, intake gaskets and any other place that would have vacuum (Be light with the carb cleaner) if there is a leak the rpms will increase and that is where the repair would be needed.

 

....As an added note, I had the same problem on my 66 Pontiac I finely found the problem was a crack on the underside of the intake manifold. After cleaning the crack and cutting a small v-grove into the crack I filled it with JP weld and had no more problems.

[mpalazzo]

Thank you so much for your input! I will resume working on it soon let you know how it goes!