Im lost! 1986 S10 Blazer ..

[SLO_GTO]

Yea, probably the only way he got it to idle before, just dumps fuel into the mix instead of figuring out the other issue why it wouldnt idle to begin with.

[robertisaar]

SO, now that the O2 and MAP are working, i don't suppose your scanner can put logs on a computer?

[SLO_GTO]

Unfortanly, I dont think so.
It looks like this:

http://www.northerntool.com/images/product/images/338947_lg.jpg

Its an AutoXRAY or something.

[robertisaar]

i would doubt it.....

idling at 2.6V is kind of high, translates to about 60kPa.
any more vacuum leaks you could find?
and what kind of counts do you see for IAC when at idle?
and what kind of MAP voltage do you see when you're at maybe 40MPH and take your foot all the way off the throttle and let it coast? and possibly, what kind of IAC counts do you see at the time?

see why i like laptops for logging?

[geoffinbc]

Your TPS is .88V that is WAY too high at idle. you need to adjust it withing .45 to .65V. .5V is preferred. Loosen the screws and adjust it until you get your reading spot on. The truck can be off. Next set your timing. You never said what it was you just said it was good. Did you disconnect the ECT wire under the dash when you checked it? If you didn't and it read 10* BTDC then it is severely retarded like 20* or more. So check again.

Once in closed loop O2 sensor reading should fluctuate all over. When in open loop just ignore it. On the S-10 a non heated sensor will always fall out of closed loop at idle. If you want to see closed loop readings hold the engine at 2000RPM or more. or install a heated O2 sensor.

[SLO_GTO]

Thanks for the responses by the way. Late Sunday nite, I towed the truck back to the gentleman.
robertisaar- I towed the truck shortly after your post, so didnt get a chance to check those details for you.
betterthanyou - Yes, I did reset the TPS sensor to .50volts. Thanks for clarifying that.
Timing? I did not check this myself. Had my stepfather take a gander. I did not disconnect the ECT sensor from under the dash.
O2 sensor: I didnt know that. I thought after the ECT reached a certain temp, the O2 warmed up enough, or certain time frame was reached, I thought the ECM went into closed loop, and stayed there.
I did see it kick into closed loop when I was revving it.
Is this the same on DIS (coil packs)/MPFI? Or just with all one-wired/non-heated O2 sensors?

The truck is located in the town I work in, so next time I get a chance, Ill bring the timing light and see what results I get. (Got to research how to do that first, lol)
As far as my understanding is, hook up pos/neg plugs to battery, and other wire goes around cylinder #1 and you shoot the light @ harmonic balancer.

Do I unplug the ECT sensor off the manifold, or does it have to be under the dash?

Thanks for your help guys.

[geoffinbc]

The ECT wire is under the dash right in the passenger foot well. Pull back the carpet and you will a single wire with a black connector. Warm the engine up if you can if not don;t worry about it. Disconnect it with the engine off and the start it up again, the check engine light will be on. Now check the timing. You are looking for 8* to 12* BTDC on the pointer. If you don't see it then it is probably retarded. So shut the engine off, loosen the distributor clamp (15MM) and rotate the distributor counter clockwise while using the light to check. Put it at 12* and when you tighten the clamp down it will shift back between 10* and 11* in my experience anyway. Now go back under the dash and reconnect the wire. The check engine light will be out. Drive the truck see how it runs. If it works good then drive around and get the engine hot and check it again when the truck is at low idle 800~1000RPM and adjust if necessary to 12*BTDC again.

[SLO_GTO]

Thanks for the explanation. I got a big work schedule on tap this week, so it will be a few days, but I will definately post my results.

Thanks again
- SLO_GTO