I have an 86 @.8 TBI S10 Blazer with about 138k miles, and i havent hadmany problems til recently. When i accelerate in 1st gear, no matter how smoothly i engage the clutch, it bucks. When i shift into second and get higher into the gears it doesnt do it. Ive replaced the 02 sensor and checked my plugs, they are fine. I looked at my injectors and they drip at idle but when i get on it i get a nice conical spray.
Another problem is when i start it on a cold morning it starts strong, no problems. That is, until it gets into an idle cycle. At this point, the idle fluctuates and a few times it has threatened to stall. I get a gas smell and occasionally a SES light.
I love this truck alot and i hate to see it run bad, help?

 

If you look into the throttle body and open the throttle plate, do you see a lot of black carbon build-up?
My thoughts are to clean the throttle body andIAC valve. Another thing I would check the TPS with an analog voltmeter and check to see if it's smooth from closed throttle ( about .5 volt ) to wide open throttle ( 4.5 to 5.0 volts)

 

The little bowl thing is clean as a whistle, i was amazed at how clean it was when i first saw it. i havent looked down beneath the small valve though. where is this TPS and IAC valve located? Thanks for the help!

 

I haven't got time to go through all the details at the moment ( Christmas season has begun)

Here's a pic of a throttle body with the IAC and TPS.
I would also suggest that you buy a manual for clear testing details ans knowing what tools are needed.


[IMG]local://upfiles/2910/EC5DB74D623B4945BA499FA11C88BF4B.gif[/IMG]

 

i put in a thing of the expensive fuel injector cleaner and that helped alot. It still does it periodically, but not enough to really matter. I want to clean my EGR valve and the MAF sensor, i know where the MAF is, but im not sure at all about the EGR. I looked at the diagram on the sticker in the engine bay and it pointed me towards the brake booster...again, its an 86 S10 Blazer with a 2.8 TBI V6.

Another thing, where could i find a diagram of vacuum lines?