hi i just bought a 85 iroc tpi with a 5 speed last week. my problem is that when i stop at lights or a stop sign it idles fine but when i go to take off it seems like it aint getting gas or something because ill go to take off and it will start to hesitate forward then all of a sudden it bucks like a bronco and then hesitates again but eventually goes and when i get up to about 30-35 miles an hour it runs and accelerates fine. Can someone give me some ideas what they think is causing this because not only is it annoying its pretty embarrassing too lol. it only started doing this yesterday night.

 

i should also mention that it starts right up even if i havent driven it for a day or 2,and this is my first TPI 3rd gen i had previously had an 87 z28 with a carb so i dont know alot about TPI.

 

R U sure its a 85 IROC? IIRC, the 85 IROC came out of the factory with a carb. But if it is a TPI,then either of these sensors may be bad, MAF Sensor, TPS, Idle Air Control Valve, or the timing is off.

 

yes its a 85 the PO did a tpi conversions some years ago before i got it, and from what ive read in 85 the iroc was available with TPI but only with an automatic tranny. but so those sensors or the timing can just go out like that without any warning?

 

OK. Well hopefully the PO connected all the wiring together correctly. Does your SES light work? If it does, it should display troubleshooting codes, IF it is wired correctly. Givin that you have a TPI, The ECM must be a 7156 or a 7730. These ECM's store troublecodes. Ground out terminals A & B in the ALDL port and tell me what codes you get.