NEED HELP 350TBI

[slim69]

ive sprayed the hole motor and all the hoses and no change all vacum lines are good

 

[StreetBu]

Here's one that's going to sound very odd, but easy to do. I'm guessing the truck has a/c? Find the a/c line that has a switch in it and unplug the connector to the switch. See if that fixes the problem. The switch and the the IAC share a common ground (I think, It's been awhile) and I've even seen the a/c pressure switch fail and cause idle concerns. This is more popular on fwd GM cars but it's easy and worth a try. Let us know how it goes.

 

[slim69]

i unpluged all the ac switches and pulled all grounds off and sanded to make sure i have good grounds and pulled the hole wiring harness up to check for broken or messed up wires and put a new ecm in and it still the same. I GIVE UP!!!!!!!

 

[big-angry-hillbilly]

Isn't the base timing supposed to be set at 0* with the spout unplugged?

 

[Doober]

Factory yes, but I found mine was much more responsive at 10-12º advanced.

 

[slim69]

i finally got it to run at 0 but it doesnt run any better

 

[injected]

I GOT A 95 CHEVY TRUCK WITH A TBI 350 THAT RUNS LIKE CRAP AT IDLE UP TO ABOUT 2000RPMS IVE CHANGED THE FUEL FILTER PLUGS WIRES CAP AND ROTOR THERES NO CODES IN THE COMPUTER AND THE FUEL PRESSURE IS SPOT ON I CHECKED THE TIMING AND IT IS 10 DEGREES ADVANTANCE WITH THE BROWN AND TAN WIRE UNPLUGED AND THE TRUCK WILL NOT STAY RUNNING WITH ANY LESS IT JUST SURGES UP AND DOWN AND DIES SOMETIMES WHEN U PUT IT IN GEAR ANY HELP WOULD BE APPRECIATED

First off all its not suppose to be at 10* but 0* with the tan wire unpluged !! I'd start there and try an other computor (bowroad).You have to start with the basics.Egr valve not stuck,vaccum leak,put a scanner on and look at the parameters.Sometime sensors are off but not busted and the computor does not make the difference !!

 

[slim69]

ive went as far as putting a new computer in it and wiring harness the transmission is doing some goofy stuff to so im thinking the two are related ](*,)

 

[cttandy]

With age, it is pretty common around here to need to rebuild the TBI unit. Can cause all sorts of odd problems.

The dirt doobers around here pack the TBI units full of dirt in all the vacuum passages. Also, there is a tiny little filter in each injector. A rebuild kit is only like $35, and includes everything you need except something to clean everything up.

 

[slim69]

i alredy did the throttle body brand new injectors and cleaned the crap out of it and all new gaskets