Vacuum leak near throttle positioning sensor
 

Hi I have a 1986 Tahoe S-10 blazer with a 2.8 litre v6. I ran into a problem with it on the way home from physical therapy one afternoon. Running down the road at 60 mph it suddenly acted like someone pulled the plug on it lost most power and had to limp it home on the side of the road. Well long story short after alot of parts and money it now runs again but idles rough , though throttle body was a little dirty so used cleaner only to find out the tbi gasket was junk. Replaced gasket but still idles rough till i spray cleaner near throttle positioning sensor...any ideas as to what could be the problem here. Any help would be appreciated. :(

Well I see this site was very helpful I'm So glad I posted On here cause i got so many helpful suggestions (yeah right) what a totral waste of my time.

If I were you I'd post a pictorial with all the areas pointed out that induce the change in rpm during the vacuum leak test. On a different note, I do believe the TPS for this truck comes with an o-ring and it might need changing in yours. I know for a fact that I have a leaking TPS o-ring but my LTFT doesnt seem affected by much.

I had a huge leak in the contact area b/w my snorkel and the throttle body, but that was remedied by use of blue RTV. You could have a similar leak. Just take a can of brakleen or TB cleaner and goto town on your throttle body area :)

So,il help you even though the 6 days you spent waiting on us to post then complain you could of researched and found the issue. anyways.

replace the throttle body. its got bushings,and a rod that runs through the throttle body. they can wear down and cause a leak. tps is fine. it rides on that rod. replace the whole thing and roll. Good luck

Already replaced throttle body this is the newer one that has the leak and oh thanks for taking the time out of your busy schedule to reply to my already researched problem. if the answers where out there do you think I'd be posting on here.

Well, having a f$$$$ing attitude on here won't get u anywhere!!!::icon_screwy:this forum is extremely helpful, however at times maybe not soo much!!! The one thing u need to keep in mind is how u word your questions......& btw..., if u get no response well it could be either nobody knows the answer or it could be that people are busy!!! :icon_rant:I personally have a friend on here that is a certified mechanic that I've had the pleasure of meeting ....& I'll tell ya without him I probably wouldn't have figured out a lot of the issues I have had!!! My apologies:icon_tongue::icon_slapcry: if I took u wrong , however u come off like a pissy teenager :icon_rant::icon_couch::icon_slapcry:

Well i'm not a pissy teenager and it did rub me the wrong way that someone would assume i didnt take the time to research this issue since i've been working on this for 2 years now,And sorry about the rant was having a bad day ,working two jobs and trying to get this fixed on whatever spare time i get ,gets tiresome sometimes.