ok i have a problem with my truck 98 5.2 4x4, when i start it on a cold start is idles normal for about 30 seconds and then the rpms drop slowly, sometimes droping down to 400, then it just revs up and fixes itself. also when i drive cold i will press the throttle to accelerate and it will nearly stall out on me. so far ive cleaned the iac, fuel injecoctors and ran 1 full can of seafoam through it, my mechanic tells me that it could possibly be the map sensor, does this sound right to you guys and if not what should be the next thing i do.

 

Are there any stored codes?

 

no there isnt

 

Could be. I've got 182k on mine and not had these kinds of problems (or ones similar to IAC issues). So I may not be the best to help on that one. With the amount of trouble some people seem to have with the IAC, and your mechanic saying that, I'd probably start there.

 

tps?? you think?? i hear weid things happen... in park if you rev the truck up to 1500rpm and hold it there, does the rpm go up and down?

 

no it runs perfect just when you first start it or accelerate for the first time but once that it over it runs like a top

 

if this was an old truck i would pin it on the carb but try setting your idle higher

 

ok i checked this and yes it does do this how do i fix it

 

Try cleaning first, It's in the DIY. If that doesn't work replace it.