hello, Im not good with the ignition system.
I did a compression test on my 87'BII took one plug off at a time and checked the compression. it was late so I left it. after work the next day, I put it all back together. and no sparky

Now its more than 10 days later and ive bought a new coil it gets power and puts it out. My TFI module checks good with an Ohm meter.Ive taken the computers out and the look good but thats just visual inspection(and they dont smell burnt). Last night I took the spout connection out and checked with voltmeter and its getting the signal to fire(the TFI). IM STUMPED and mad................ I think the BII nows ive bought a blazer..chevy blazer

 

I love how no one has bothered with this thread. I now Ive looked at others and stuff. like this but . hey yal . this ignition sucks After I fix this thing Im going to sell it. if anyone wants it. I really need to make some enemies some time so I can give them this truck. or maybe they would turn into my enemy after I gave it to them.? Piece of total crap. but I love it I dont now why

 

Have you checked the engine block ground?

 

Check to make sure you didn't pull the spark plug connector out when you pulled the wire off... I had a few do that. They get so hot that when you pull the wire off, the metal connector inside separates from the wire. Just check each wire with an ohm meter.

Another thing... When you did the compression test, you did pull the fuel pump fuse right? If not, you may be flooded out, or really fouled your plugs.

Check around for disconnected sensors... One might have come loose when pulling the plug wires.

P.S. you only waited a few hours before flaming us. We don't sit here just waiting for someone to post. Take your time, kick back and have a beer.

 

well hello. everyone. I really havent had time to look at it but. the plug wires are all good. the ground is good. I did look at all that. Also I did unplug the fuel pump relay. I have pulled plugs back out and they are getting wet with fuel when I crank it now,. Im thinking the stator or maybe the computer. My codes read that the coolant temp. sens. was out or over/under. also the map. sens.was failing.(but that was when it was near 0 degrees out.) I know everyone is dieng to find out if it will ever run again. so Ill keep you posted.

 

KOEO ECT codes are usually caused by performing the KOEO test on a cold engine. Of course, when the engine won't start, it's going to be cold (unless you take a heat gun or something to the ECT and warm it up. I doubt the ECt code has much to do with your no start, though I'm assuming a few things because you didn't post exact codes.

What MAP code did you get? 22? Was it a KOEO or CM code? While I know I've been able to start mine without a MAP, I could see where a bad MAP signal could contribute to a no start condition, if it causes the computer to dump way too much or way too little fuel into the cylinders.

 

yea, I think it was code 87 or something. just from memory.It I believe is all just out of range. There is just no spark coming out of the plug wires. however it all works? Whats the stator do?

 

It seems to me maybe that the TFI module might just monitor the spark ignition instead of deligating the spark out? maybe since the coil is puting out power it has to be pulling through the plug wires? Tell me anyone what they think. tell me what the PIP signal is? I Beleve this is like the timing or something? The TFI recieves this signal from the computer? I know my computer and ignition have power so does the TFI.

Does the stator distribute the spark to the plugs? Could it keep the plugs from the spark?

 

According to my code list, a KOEO 87 is a fuel pump circuit fault, and has nothing to do with the MAP. Of course, a fault in the fuel pump circuit could certainly cause a no start, but the spark plugs should still fire.

Are the ICM and fuel pump relay getting power from the EEC relay?

 

I must be mistaken about the code # It for shure is gating fuel. without a doubt.

 

Still want to know if the ICM is getting power.

I'd probably go back and re-read the codes real quick just so we all know what they were. If you really did have a MAP code, or certain other codes, I could see that helping us know where to look for the problem.

 

Just wanted to update i've been to busy to really get down to fixing it. I put a new coil in. and there is actually no spark coming out of it. So that is defferent than what I posted before. Now ther is power gatting to it, but there is no signal from the TFI module there is also no signal coming through the spout conector going to the TFI module. My newest question is how to check the computer If there is a TEST.

Really want to now what if there is anything that tells the coil to fire or if it just should, if it has power going to it.\
also just so everyone knows these codes specifically are 21/22/87 thats KOEO.
the fuel pump code is there because the relay won't switch it on unless I ground out Pin 22 side of the relay. Ive had it this way eversince I gave someone a jump and it blew the relay. it has ran like this for awhile.what I dont understand about it is that there is 12 volts threw the relay and it wont switch. Ive tried 2 different relays and still would not work.

 

ICM/TFI module is what tells the coil to fire. If there's nothing between the ICM and the coil, then that's why it won't fire. Is the TFI module getting power? Ground?

With a couple of exceptions, there really isn't a test for a bad PCM (except maybe the "guess and check" method). The usual test for a bad PCM is to eliminate all other possible causes of the problem, and then the PCM is bad by process of elimination. At this point, I don't know that we've really gotten close to a point of saying that the PCM is bad.

Did any of those codes come up in CM as well (after separator pulse) or did you get a 11 pass from CM?

Both the red and tan wires at the fuel pump relay are supposed to show 12 V all the time with the key on. Your description suggests to me that there's a break in the wire to the PCM, a bad power/ground to the PCM, or a bad PCM or something like that that is preventing the PCM from grounding the circuit to close the relay. This might be related to the no spark, as the computer doesn't want to close the fuel pump relay until it sees the PIP/TACH signal from the ICM.

Are you certain that the TFI module is getting power? Check the coil ground as well. If I remember right, there's a test procedure in Ken00's tech info post for testing the TFI module with a standard DMM.

 

well from testing at the computers hareness I see no PIP signal I thought the TFI was getting power but, not confident. Ive tried regrounding the coil, no-spark. Also I know the computer is getting power.
i might try grounding at the harness for the fuel pump.right now grounding it by the relay/to fender makes it run the whole time the key is on and Im running it with the relay in. so i know thats not right .but there is defenetly 12v at the switch(tested-relay out)
so that is 1. computer problem I for shure know of.
Ive got a more detailed schematic now of the TfI, and all the wires running to and from. So i plan on working out all the details soon.
Also Ive tested the TFI with the ohm. meter and It checked good. and now I've found another kind of test to try so will see (I secretly thought it has to be the TFI, or computer.)

 

I checked that the TFI module is getting power and it is everywire has the right stuff going on. except the green/yellow wire nothing goes threw it. It is the wire that tells the coil to fire. I checked it at the computer w/a volt meter and nothing is coming out. My schematic says there is a resistor Titled: IDM, inline after the computer. I'm not shure what this is.

I also tested the TFI w/ an alternate test and it's good. Im going to research this IDM/ it could be related w/fuelpump.