cranked ty with jumper wire still in obd1

[Flip#32]

accidently I started my ty right after checking for any codes, It cranked right up, but sounded funky, and the check engine was going nuts. I knew something was wrong & shut it off. I then noticed the jumper wire was still in the obd1. Damn I am so close to finally fixing all of this ones issues, now this.. I pulled the jumper wire out, but it hasn't hit a lick sense. All fuses checked good, its getting fuel & I wanna say it isn't getting any fire to the plugs. I pulled wires off, cap off, rotor button & ignition module out. Yea, im a real mechanics nightmare. I thought I had replacement parts in stock, but only had a cap. Im currently reassembling the distributor (with its old cap) so I can double check that the plugs are truly not firing. If it has indeed lost fire, could I be going in the right direction thinking the ignition module has died? Maybe fried the computer itself?

 

[Slyclone]

I think if the tach bounces during cranking the ICM is toast.

 

[Static]

I think if the tach bounces during cranking the ICM is toast.

Its the opposite. If the tach is NOT bouncing there is no pulse signal to fire the injectors, usually the ICM. However Ive seen plenty of nasty looking pickup coils.

 

[wildphil]

You may save yourself a lot of work if you begin with trouble isolation when you have a problem with your truck. Instead of disassembling parts when the problem is unknown. More problems may be created.

One way to check if your truck is firing would be to remove a wire from a spark plug. I normally use the wire to number 1 cylinder. Because it is easy to access. Insert a screwdriver in the boot far enough so that it contacts the terminal inside. Then place the screwdriver close to bare metal attached to the engine(like the exhaust manifold). About 1/4" space between the screwdriver shaft and the metal is good. Have someone crank the engine. If the engine is firing, you will see a blue arc in the gap between the screwdriver and the metal object.

If you have a spare spark plug lying around. It can be inserted into the boot of the plug wire. Then placed with the metal of the spark plug contacting bare metal on the engine. Crank the engine and it should have spark if the engine is firing.

 

[Flip#32]

ok a new ignition module was the corrupt. New map sensor, double checked, hell triple checked the fuel pressure, vacuum lines, plugs, wires everything except the oxygen sensor. Yet it still runs rich & throws 33 & 45 codes. I give up

 

[Flip#32]

fuel pressure reads 40 (jumps between 38-42 while running) and with vac off & plugged. I guess ill go buy a oxygen sensor huh?

 

[Static]

What is the MAP sensor is it? 2 bar 3 bar? Ive seen some junk maps where the body leaks. If the vacuum is low to the sensor it will throw a code 33. Silicone vacuum line kit really helps these trucks if you dont have one yet.

 

[Flip#32]

The MAP was a $15 2bar ebayd unit. I hear ya on the vacuum lines. I wanna say, i actually saw one of its Silicone vacuum lines trying to collapse while it was idling. I assumed they do that when they are in fact needing to be replaced? Its got to be something simple, there is only so many things that can go wrong. I just wished I knew of someone local I could just drop this thing off too & let them figure it out.

 

[Flip#32]

installed o2 sensor today, didn't change anything. im done. I have checked everything there is to check, bought new sensors , I apparently have met my nemesis. Fine now goodby, see it on ebay tomorrow.

 

[fauXGT]

Check basics? Something that threw me for a couple of years was the TPS setting. My issue was very lean at idle. Finally checked the voltage out at idle was 1.5+ volts. Idle should be adjusted to about .5 to .6 volts. It was telling the ECU it was at mid to full throttle but was idle with butterflies closed. I had to file out the bolt holes quite a bit to set. Maybe opposite adjustment in your case? Keep trying before throwing in the towel. These trucks are finicky.

 

[Flip#32]

ive been under& over this one for 7 months. Ill check the TPS tomorrow. It did show me "what it could do" for 3 seconds, a month ago. Ive been trying to get it back to anything close to that. It got my attention, as I had NO idea the frontend of these things even could come up that far, being awd. I thought WoW. For 3 seconds there, it pulled like a freight train. Running right or wrong, it has to be put up for sale. Someone will get a buy on this'un.

 

[wildphil]

Don't give up now. If these are the only issues left. You are almost done.

I have been sold the wrong O2 sensor before. The parts book had the incorrect part number. That was great. Here are a couple of links that tell a little about the trouble codes and voltages that are expected. Hope they are helpful.

http://www.syty.net/forums/forum/sy...109099-obdi-and-abs-trouble-codes-error-codes

http://sytyperformance.com/syty_troublecode.pdf

 

[wildphil]

Is this the truck? If it is I guess you were not joking about being done with it.

https://www.ebay.com/itm/1992-GMC-T...ash=item2aae2de97c:g:p3wAAOSwK8BbP17A&vxp=mtr

 

[Flip#32]

that is it sir. done, well i paid a guy to finish the a/c today. blows on the bottom, but i think that's a ez fix. If you know someone that wants a hellOFadeal it could be bought for less than ebays posted price

 

[Flip#32]

well I swapped the MAP sensor for one I had in stock. Probably not the correct one but WOW it stopped its running rich issues. Runs good BUT doesn't wanna build any boost. But compared to how it was running, ill take it. Still on the chopping block though~

 

[Slyclone]

I bet you it's a vac line or a plug wire causing havoc. Something so small you wouldn't believe it.

 

[wildphil]

I believe all the issues you are describing are minor.

If your truck does not sell for some reason. Start a new post about those issues you are currently having and we will try and help you get the truck repaired.

It could be problems with vacuum lines causing both your issues. More info and some testing would be needed to be sure.

 

[Flip#32]

while trying to figure out why the a/c(now cold) only blows out of the bottom, I found a vacuum line sucking air. And there was a nut stripped out on the clamp that connects the garrett cooler to the throttle body. I understand that I maybe really close to getting its 99problems figured out, but its time to let it go. Any confidence I had i lost back in April. I truly didn't need this 'deal of a lifetime' at this point in my life. As I am dealing with other issues~ thx for real for great advice, yall nailed it. If & when it sells I gotta post what I paid for it. When I told my closest buddies what I paid they said 'Really? Wow, yea itd be kinda hard to pass on a deal like that". Im guessing by auctions end, it will truly be tiptop.