ok still cant figure out my 88 iroc 305tbi.I have tried everything. still when it starts the rpms go crazy up and down. Any suggestions would be great.
Any local Clearwater, fl guys that would like to stop by I would be very greatfull . Please help me get this thing back on the road before it goes to the scrap yard I cant be with out a car much longer.

 

when is the last time you did a tune up on it?

 

promblem started last week it died driving ,i have since done cap, rotor,plugs ,o2 sensor airfilter, egm valve. Cleared all codes and still nothing. It is getting fuel and spark, fuel pressure is 12 psi. battery is good,

 

Does it display an SES light? Could possibly be the throttle positioning sensor, or TPS for short.

 

it does not show any codes now
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what years could i use the tps from a may make a junk yard run because no one has them in stock . that way I can test it before I spend another $40

 

https://www.thirdgen.org/tpimod2

This will show you how to test it without even bothering with a boneyard.

 

i will try this now

 

do you need 3 jumper wires and could you guive me a little more info on where to hook up vom. sorry I am auto mech challengened

 

https://www.thirdgen.org/forums/tpi/...tps+adjustment

 

Testing with a VOM? Follow the tech article posted by Viprklr.
The TPS is located on the passenger side of the throttle body. Has two screws securing it, and one wired connector. Disconnect the wired harness, make your jumper wires, turn key on and test voltage reading while opening and closing the throttle.

If it's bad, you can probably find a replacement part at Advance Auto for around $20+-.

Good luck

 

ok no jumpers unpluged key on I get 4.5 with pos on c and neg on a. aand b i get nothing with or with out junpers

 

ok I got frustrated and removed the tps and it did not change to much it idled lower but still rough

 

tps off car, jumpers between all 3 leads I get 4.99 volts with a and c and nothing with any other combo

 

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ok here is everything I have replaced
cap
rotor
plugs
tps
tps plug
fuel pump relay.
o2 sensor
air filter.
it ran last night befor i put the tps on then it would not start again so today I picked up the tps and still will not start.
if noone has any clues the tag is coming off and it will sit untill I have time aND money.

 

Check the vacuum lines and replace the pcv valve and see what happens.

 

would either of those keep it from starting

 

if you had a big enought vacum leak then yes it could make it not start.

 

ok just got help from a guy with a couple fbodies. He determined I had weak spark. if you hold the coil wire away from the cap it starts and runs fine. he tried a ne coil, new coil wire and it was still the same thing. any ideas