I replaced my sorry 305 with a remanned 350 out of a Caprice LTX Police Version.

Added headers & dual 3" exaust with a high flow cat.

Tranny rebuilt with a vette servo, shift kit, & 2000 stall converter.


Even had done some chip burning.

Here is the problem.....


The car runs fine at a idle. The car runs perfect moving down the road. BUT it dies everytime you shift out of park or neutral or come to a stop with the car in gear unless your gassing on it at the same time.

Right now, this is my only hold up.

Anyone have a clue about what I should do or look?

 

You could try raising your idle a bit -- it may be that as you shift into park and your idle rpm decays towards idle on slowing down it dips down just low enough to where it stalls out the car.

 

Any details on how it dies? Does it just crap out or does it sort of make an attemp to stay running and then die. How old is the IAC?

 

The IAC is new. It was replaced with the engine along with knock sensors and such.

To me it seems to just crap out. If i'm on the gas it will stay running, but who wants to stand on the throttle when sitting at a stop light?
OK, well that is a little fun with the locker in the rear but I honestly don't think it is legal.

 

How high does it idle in drive? Does it idle well? There are some things in the calibration that can cause a stall, like IAC pump shot that will be added in when the IAC opens.

From your last statement you make it sound like it peels out when you give it gas at a light to make it idle. If this is so, then the TC cluch is locked and preventing the motor from idling. Real test is to stick it in D, 2, 1. Itll feel like a manual trans with the overrun clutch locking the sprag.

 

It doesn't idle at all in any of the gears, Unless your on the throttle. you let off the throttle & hold the brake normally & it dies out.

It idles pefectly in park & nuetral & always restarts after it dies out.

I had someone else tell me that my converter may be causing the problem. I don't know?
I know that I have over 10K in this thing right now with everything I have done & this is probally something very simple & inexpensive.



I was trying to make a joke to make myself feel little better. It will burn the tires pretty good with a decent power brake.

 

oh, ok.

hmmm... It could then be a problem with the timing, or the fueling. Too little timing in high map area where the car would idle will cause the motor to die. That would probably be one of the first things Id look at, assuming it is a problem with the tuning.

Try this: With the engine warm, disconnect the EST connector and temperarily move the base timing to ~20 degrees BTDC (dont drive the car like this). This will temperarily give you a flat ammount of timing at idle. Try sticking it in gear at idle then and see if it does any better.

 

Did you use the injectors for a 350? The LTZ was 180 fwhp and 300 fw ftlbs.... and did you use the correct injector const in the ECM?

BTW, the base timing should be 0 deg with the dist wire disconnected. That's the correct timing spec for LO3/LO5 swirl port heads -- they don't need as much ign advance.

These don't explain why the engine should stall as you describe but I think you might have more than one problem.