Phoenixfire1989

I just got my car back from the mechanic after he replaced the intake manifold gasket and the injectors in the throttle body. I got the car back and it was stalling out. It felt like when i pushed the clutch the rpms would drop all the way down and not catch itself stalling out. It does it more so when the AC is on. I brought it back and he said the timing was off 2 degrees to compensate for the leaking gasket from the last owner. I got it back and it still stalls now and then.
When i start it after i had it running..it turns over very slow, then starts(especially after it's stalled). My oil pressure is at about 30 running, but drops right above the red zone while idling. This is also something new, but might be coincidence.
Mechanic said it's an old car and when you start changing things sometimes they throw little fits cause its been running a certain way for so long. Can the oil pressure be stalling it? or does anyone have any other suggestions. Car is 89 formula, TBI 305
oh i forgot to add it idles up and down..just enough to make the rpm pin twitch. especially when the AC is on, but my dad said this is normal for it to idle up when the compressor kicks on and to shake?

KITT1983

iTrader: (3)

i have a similar problem but my is 1983 ta crossfire injected

Phoenixfire1989

Yesterday a new problem has occured. When cold, it starts right up. When i take the car somewhere for a couple minutes, then come back out to start it, it turns very slow and won't start. Car is in the shop today. Thought it was the alternator, but i checked the battery after driving it and im getting 12 Volts..so i don't know.

Camarillo

The loping idle sounds like a vacuum leak (up and down). The hot start sounds a bit like ignition issues (maybe).
Check the ignition control module ICM and the pick up coil on the distributor.
There is special thermal grease under the Ig. cont. mod. that can dry out causing hot start and hard start issues.
I had a similar problem that was solved with grease/replacement of the ICM

Phoenixfire1989

well the idling problem has always been. The antifreeze was starting to leak so my mechanic replaced the manifold gasket. I just had it at pepboys for 2 days because my usual mechanic is overwhelmed with other things till next week. They said my starter went bad. This is the 2nd one since december. They said it's still not starting like it should, but it starts. They said they have no idea what is wrong with it. Im not surprised...in the least. At least the starter and labor has a warranty on it.

Camarillo

A starter should not be causing a stall, I don't even think its possible (but I am no guru).
An erratic idle is usually a vacuum leak, either a hose is broken worn or disconnected, or a gasket is bad some where, like in the TBI system.
Have you inspected your coil, ICM, pick up coil?
Has the timing been set properly, following the intake install?
Note, I also saw a "twitch" in my RPM needle when the ICM was compromised.


Has the TBI unit been rebuilt? Or just cleaned out really well? Throttle body spray works wonders on clogged and sticky throttle components.

Here is my TBI basic cleaning procedure
Remove air cleaner housing, air filter, so there is open access to the TBI
with engine off, negative cable disconnected, manually open throttle wide open,
SPRAY the inlet in bursts around all pivot points and the butterfly blades
Spray all deposits away, wiping as needed for excessive grime.
Clean out IAC, idle air control valve, port. actually removing the Connector and valve itself and Spraying from both sides works best. Re-install after cleaning this section.
Then I quickly spray the sensor in the Air Cleaner Housing, the vacuum one with a hose coming from TBI, one for THERMAC.
Then I spray the external linkages to free up any dirt or grease accumulated.
Connect neg cable, then I start the car and spray into Vac lines going to TBI, from PCV hose(remove pcv), hose from Sensor on air cleaner housing, and all ports on lower front of TBI. re connect pcv and all hoses.
By the way make sure you block the tires
Then I pull the vac line after check valve, from the brake booster on firewall, and finish the spray into this line(going TO the intake manifold), while setting RPM at 2100-2500.
Make sure all parts are properly re connected and re installed. Make sure no breaks or tears occured in any vacuum lines

Phoenixfire1989

Mechanic just replaced the injectors in the TB. He's a really old time mechanic and is very thorough. The car is rough idling, stalling when the AC is on. My oil pressure is now reading 0 while idle, and is just above the red zone while in motion. I just changed the oil and such, so that's not causing the problem(thought it might have been a clogged filter). Now around 2300 and above im getting a grinding sound, even if the car isn't in motion and i just rev it. It's really concerning me. It's making almost a backfire sound while just sitting that is shaking the exhaust from the catalytic converter back. Im really awful with cars. I'm just hoping my engine is ok. I think it's the timing. That's when all these problems started. Thanks for all your advice! it's really appreciated. Any suggestions on the oil pressure issue?