my car is stalling out for some reason, when my car is under heavy load (such as going up a steep hill) or I just punch the gas pedal and then just let go of the pedal the car suddenly stalls out and does not return to idle or I am at a stop light the cars idles real low at 400-500 rpm. what could cause this?

fuel pressure?
vacuum leak?
slow leaking thermostat housing?

 

I've had a similar problem with my '83 CFI. I found early on a CFI motor doesn't like vacuum leaks of any type. I replaced all the vacuum lines along with the intake top lid seal which helped immensly. EGR section of the manifold can cause issues but I'm not had them yet. Have you checked fuel pressure? The factory CFI spec is 9-13psi. It maybe as simple as a clogged filter. The F-Body's CFI filter are hard to find but the '82 CFI Vette's filter isn't oddly enough (though they are a bit different). If you have a fuel pump problem then it's best to upgrade to a '85 TPI pump. The other cause could be worn throttle shaft bushings. This will cause all sorts of issues including rough and/or erratic idle and if bad enough stalling. I don't have my computor for the link but I believe this is their new website http://crossfireinjection.net/ I hope this is of some help.

 

it could be the shaft bushings they stick time to time usually during the spring or fall but this has never happened before

i just replaced the A/C vacuum selector switch, which helped.

I guess one of the plugs might of gotten loose
my EGR/AIR pump is disconected and the AIR tubes removed and plugged

my fuel filter is new and napa sells them

my fuel pump is new a stock 1983 acdelco cfi one but i have heard of the 1985 corvette TPi fuel pump upgrade

 

I think it is the IACs or a vacuum leak someplace.

 

Definately check for vacuum leaks and replace your vaccum lines. You can use carb cleaner to check for vacuum leaks gound the base of the TB's, shaft areas, and the like. Be careful around the distributor though as I caught my engine on fire.

I had my TB's rebushed by CFI.net and balanced them when I reinstalled them. My engine liked to surge which I think might have been due to the cam that was in it and larger injectors with a 305 tune (had a 350). You can pull the IAC's and clean the ports. I would also look at cleaning the throttle plates as well.

I also did the TPI pump mod and it improved my top end power so I figure my factory pump was a gonner. When I did the LT1 conversion I found my tank full of rust so I cleaned and coated it. The rust was packing up my fuel filter.

 

The IACS are clean and readjusted the idle it worked fine for about a day and now it worse then ever.

When I start the car it goes to 700 rpm and shakes violently. While I am driving the car to work, it is ok until I hit a stop light or at the rotary and it wanted to stall out. It went to 300 RPM and bounced back. On my way home it stalled out twice. (I had my A/c on) and the whole car shook violently.

 

I replaced both iacs the passenger side is dead and the drivers was tired and clogged with carbon build up. the motor ran better but there is till a rough idle. would a 160 thermostat cause the rough idle, closed loop problems or spark plug fouling ? Is lucas good for fuel injector cleaning

 

i really need help here

 

How old is the TPS? Test it with a jumper. Should increase voltage with key on engine off smoothly from .50 up to 4.5v. You may find a dead spot.

Also pull codes if any. auto parts store can do so.

fuel injectors lookat visually. should be nice even conical spray. No dripping.

 

The spray from the injectors is conical with minor dripping in the center. There are no codes and I have a scan tool for OBD1 and the OTC OBD1 jumper key reader tool.
Thanks, I will test the TPS tomorrow. I have a crossfire TPS and specialty TPS tester harness

 

the tps is a year old and still no codes

does any know where i can get a egr connector ?

who makes a good stock replacement cfi front and rear injectors

 

Bump

 

Your 160 degree stat may be causing problems with drivability, not sure on that. I ran a 180 in my car and ran the fans to come on about 195. I am sure you are probably still using the factory mechanical fan.

Did you clean the TB's while you had the IAC's off? Have you cleaned the throttle plates? That can also cause idle issues. It is usually not a problem with TBI cars since the injectors are over the plates, but take a look.

Have you balanced the TB's? That can cause off idle drivability problems and a stumble.

Make sure your EGR is good and not hangining open from carbon buildup.

If you need stock injectors, give CFI.net a call and I am sure they have some, or you can have yours cleaned and flow checked.

Your EGR connector can be had from any early to mid 80's GM car with a CC carb or TBI. Just look at yours and hit the yard with a pair of dikes.

You can also seam foam the top end to get rid of carbon build up. Might be a good idea to pull your plugs and look for fouling. My CFI motor was burning oil and fouling a plug.

 

fuel injectors... fuel injector connection. called FIC on the forums.

turbo city has connectors.

yes replace the 160 with a 180 for sure. You will see no diff on coolant temps. 160 causes engine to fall out of closed loop especially on cool days.

 

i have no smog pump and AIR lines. The EGR and diverter valve is all that is left connected.
how do you balance the tbis?

 

do you have a link to the turbo city egr connectors

 

bump