a 1989 chevy s10 blazer with a 4.3 would idle high until you put it in gear and why it would spit and sputter under load unless its cold and its wet out any ideas

 

Whens the last time a tune up was done?

 

Sounds like a mixture of a dirty iac,carbed egr,and a vacuum leak.


clean the egr with brake cleaner and a toothbrush.
( clean the little piston inside,move it in and out while doing so )

Remove the iac,spray it down with cleaner,including the hole.

Other then that,maybe remove the throttle body and clean the passages too.

high idle problems on the tbis are pretty easy to fix. if this was cpi....whole can of worms.

 

He's got an '89 4.3L.. should be a CPI intake. What entails the whole can of worms? I have close to the same issue, even after changing my MAP sensor and IAC.

EDIT: My tune-up was done last year, less than 10k miles ago

 

no the 89 4.3 has a tbi unit.

 

thanks guys il give it a try

 

Harlen, did you find a solution to your problem? Mine is doing something similar.

 

Since his is an '89 and you have a '97 with a completely different injection type, I doubt that there would be a common solution.

 

Not necessarily true? I have an 89 and it has TBI all day long. So I don't think the year defines that it must have the CPI in it? CPI is only Vortec, right?

He will wanna make sure the EGR is functioning as well. See if it holds vacuum. Also, may wanna try new wires, along with new plugs, and make sure the timing is on the money. 0 degrees with sprague wire unplugged. I can't tell you how many times I hear the word "sputter" used as a problematic symptom and it be the timing was off. Hey, doesn't hurt to check!

 

I pulled the EGR off and cleaned it with some throttle body cleaner and a tooth brush. I haven't had the sputtering happen again. Only been two days through so time will tell.