Chris_1

iTrader: (1)

Theoretically, the vacuum system is one single system and a leak anywhere will cause the whole system not to develop proper vacuum - but - some of the lines are closed off at certain times because they're controlled by switches.
Mine runs 15 at idle, 10 - 11 as I open up the throttle, and about 20 if I back off when I'm moving (like taking your foot off the gas going down a hill).
That's at the tree on the upper intake.

KurtH

And I had some time today. Last week out of desperation/frustration I did order an IAC, and a TB gasket.

I removed the Throttle body and the back side past the throttle plates was filthy, as well as the back of the plates. I cleaned it as best as I could with chem tool and a tooth brush. I got all the crap off it and it was just about as good as new. I also cleaned inside the area in the intake manifold just behind the TB. I ran out of chem tool before I could get that area perfect, but it was much better than before.

I put it all back together and it settled in and seemed to run OK. It did throw
122 again (Throttle Position sensor below minimum voltage) but I decided to take it for a ride. I drove around my residential area, and while at stop signs, the idle did not surge. It ran quite well. I parked in my drive way and let it idle for a few minutes, then stepped on the clutch to back up, and the idle started surging and the CEL came on and stayed I backed it up and then moved it back forward, and turned off the engine to pull codes. Using the Innova code reader, it went nuts: (this is KOEO not continuous memory)

117 Engine coolant temperature sensor below minimum voltage / 254° F indicated
126 Cylinder identification circuit failure
122 Throttle Position sensor below minimum voltage
112 Intake Air Temperature (IAT) sensor circuit below minimum voltage / 254°F indicated
327 EVP/EPT circuit below minimum voltage
513 PCM internal voltage failure
553 Air management circuit 2 failure
552 Air management circuit 1 failure
565 Canister purge solenoid circuit fault

Yikes! just about everything. so ... everything failed at once by pushing in the clutch, or there is something systematic causing the computer to loose connectivity to several sensors at once. I decided to disconnect the battery. I ended up disconnecting it for about 2 minutes, then started it again. It had a surging idle, but different this time, and the exhaust smelled as though it was a car from the 60s (pre-emissions)

It was very sunny, and it was hard to see but there was smoke coming from the tailpipe. I could not discern the color, it was hard to see the smoke in the bright sunlight, and it was casting a shadow on the ground, and it was hard to distinguish the shadow from the smoke.

The CEL came on again, and returned the same codes.

So .. how long must the battery remain disconnected?

I looked and i could see the PCM connector under the hood, the black plastic boot was not completely covering the white plastic and I could see some of the wires, as though the bolt was so tight, it warped the plastic. (too much torque in the center drawing the edges away.) So Are we looking at a loose connection? is it time to pull the PCM and check for bad caps?

The other notworthy thing is that the clutch was replaced in January, as well as the slave cylinder. I have not experienced any other issues since the clutch was replaced.

KurtH

Ok, after getting many codes at once, I figured it was a wiring problem or the computer.

since the computer is easier, I removed it first

I opened it up and found








This is two different caps. leaking and corrosion. Am I correct in thinking this could be the problem?

Thanks

I found this place with the computer:

http://www.partsgeek.com/catalog/199...trol_unit.html

any one deal with them before?


any luck ordering from them? Are A1 Cardone PCMs good?

tvand13

You could try replacing the caps for like 20 cents.

KurtH

It has been a little less than a week after installing the replacement PCM, and the truck is running fine. I have been using it exclusivley and no trouble so far.


I just wanted to follow up since I found many threads on different forums, and many times, no one posted the fix.

So if you keep getting weird codes .. check the computer for leaking caps. Resist the urge the throw parts at it.

now .. back to tracking down the reason it is blowing the brake light fuse so often.

Chris_1

iTrader: (1)

Look for a bare or pinched wire or a bad socket

Chris_1

iTrader: (1)

Thanks for letting us know the solution !

memoniz

x2

Crock Pot

Do you have a pigtail for connecting trailer lights? My son found out that exposed connectors will blow fuses when they touch metal.

KurtH

I had one ... I started tracing the wires and saw it must have had a few iterations of harnesses, I found a connector that was crimp connected , and then further down there was a mess of electrical tape, under which I found suitcase connectors. .. so two splices. I cut all that off and taped off the ends. I replaced the tail light bulbs also. If the sockets are bad is there a test to confirm?

I got so frustrated I did a silly thing and used a 20 amp fuse, which lasted much longer than a 15, but it finally blew after 2 months. Any other common places for the wires to pinch, rub, etc?