ok well i just picked up another 3rd gen, its a 91 rs with a 350, not sure what the 350 came out of just yet, but its still got the tbi, and a custom chip done by a tpi shop up near phoenix.

Questions are? the injectors are ticking extremly loud, sounnds like bad rocker arms but those are all good. Do i need new injectors, they seem to be spraying good and evenly. What is the cause of that, when i did the search for it i didnt find any concret answers.

Also it DOES NOT have an open element yet, and makes a louder hissing sound than my 92 with an open element, is it just a leak somewhere, or what is the cause of that, almost sounds like a turbo spooling up. Any help is greatly appreciated


*edit* also the SES light comes on, and it idles a little bit high, if i turn it off and restart it, the light doesnt come on, and it idle right around 600 or so. Any ideas?

and for anyone wondering, the stroked 305 vortech has been scraped.

 

the high low idle sounds like a MAP sensor to me. Pull the code and see what it is.

 

The injector tick is normal. All TBI inejctors do that. As for the hissing sound, that could be a few things. You could have a vacuum leak at the base of the TBI unit that is causing it or it could just be normal. The 350 will injest more air than your 305 did yet it is doing so with the same eize TBI unit. Therefore, more air is passing through the unit than before. TBI units are noisy in general. That is one of the reasons why the stock intake assembly was desinged as such. So your surging idle could be a vacuum leak or it could boil down to bad chip work. Unless the shop that did the chip work spent a lot of time on it (which I doubt) the tune is not right. Scan the code and find out why it is being thrown. Even though the ses light may be off the code has been stored and can be read until it is cleared. Start with the vacuum leak possibility and code and go from there. It may be a good time to get into data logging.

 

hey shifty i appreciate the leads on where to look, a vacum leak never occured to me for the hissing sound. I definetly know the tune could be better, ive played around with it a little bit on the 92, but gonna wait and do headers and open element on the 91, for some reason the previous owner used the original stock manifolds from the 305, there anemic on that engine and for sure arent helping anything on this new one.
can a vaccum leak cause it to throw a code??

 

I have had a few vacuum leaks in my day, some pretty severe, but I have never had one throw a code. You can use a paper clip to find out what code is being thrown. You can also go to autozone and have them scan it for free. Your car is throwing a code for a reason.

 

ya i know the whole paper clip thing, i disconnected the battery to reset it, and the SES hasnt came back on yet, i guess i shouldve checked for the code before resetting.

 

Well I am sure it will pop back up if the problem is there.