1994 problems.

[Rosie]

not yet, didn't have time today...will do it after work tomorrow and let ya know what happens

 

[Nhaz]

actually it does fire up then die 4 seconds later...during those 4-5 seconds it idles like crap....

i tried the engine ground idea, used a jumper cable and connected the engine direct to the battery negative and it didn't change anything...

i am gonna replace that vacuum line tomorrow and then start the long search for ground wires...

but your post kinda give me a little light seeing you said kinda what it is doing.....

thanks tonnes

Welp. I maybe missed something. Though it wasn't firing at all. But with a giant vacuum leak like that one its not going to run well. or at all.

 

[Rosie]

nope you didn't miss anything, my bad, i only noticed it myself when i tried to start it after i grounded the engine to the battery yesterday. didn't get a chance to post it before your suggestions, sorry...

havent' had a chance to get back at it yet...i will first thing tomorrow morning

thanks again

 

[Rosie]

ok, so i replaced the vacuum line, cleaned every ground i found, did continuity checks between the engine and frame, frame and body, engine and body, body and battery, engine and battery and frame and battery and i get good continuity all around.

for lack of anything else to do i poured a little gas in the intake plenum and after a few turns it fired for a brief second so now i am on to the fuel system.....

on that note, the fuel filter is new, less than 2 weeks old...

 

[Rosie]

well more of todays adventure...

its getting fuel, so i checked the plugs, 1 and 5 are dead again, no spark....tested wires, fine.....put in all new plugs still no spark on 1 and 5, its got a new coil pack that tested fine at 13 k-ohms across each pair of plug taps....

whats that condenser looking thing that plugs into a connector on the plug for the coil pack?

thanks once again all...

frustrated as can be.....

 

[Rosie]

ok so i swapped out the icm with one from a wrecker, it starts now but runs really rough and won't idle on its own. i reset the computer by disconnecting the battery over night. i am thinking the icm i got from a wrecker is better but still not good enough......

any suggestions? about to check for new or different codes...

thanks again

 

[Rosie]

ok so i still have codes 212 & 232, but not 543 anymore. still running brutally not idling running real hot out of the exhaust.


interesting note, for lack of anything better to do i plugged in the original icm again and it ran the same as it did with the wrecker icm....

also noticed my alternator was too hot to touch after the engine running for only around 5 minutes at about 2500 rpm...i mean seriously way too hot to touch. so i wondered if the alternator would have a faulty regulator and would be feeding the system with too much power thus affecting the ignition....

i unplugged the alt and fired it up, it ran smoother but still not the best so now i am resetting the comp again and will try to fire it up again without the alt to see what happens.....

anyone experience anything like this before?

 

[Rosie]

so runs and idles, still a little rough but much much better, without the alternator plugged into the system so i guess that was a big part of the problem....

those spout tabs, the grey ones, i found 2 on my truck and test both for continuity and they tested good, when i tested the wiring harness side on them i got one wire on the one in front of the battery as being grounded and both wires grounded on the one behind the battery.....

is this a big deal?

 

[Nhaz]

Yes the alternators regulator/diode pack could be down and the truck is being fed lots of A/C power instead of D/C power or both =>. Its possible to get whats called a half wave. In effect you are getting half a/c half d/c Not good for running anything => If you had a full wave a/c the truck would run right off the battery and it would go dead in a hour or so.

Easy to test for. Just run the meter in A/C instead of D/C check at the battery with it hooked up. You should pretty much no a/c its possible to have small amounts and not harm anything. but if its anything over 3 or 4 volts a/c you have a problem there. I haven't seen many alternators produce half waves. I have seen a few motorcycles do so though.

 

[fmendes49]

The relays in the relay box are all the same swap out the fuel pump relay with the ac

see title

 

[blh0007]

i was gonna mention the relays in the box under your hood... my truck had similar (not exact) symptoms and (after $500 worth of parts that didn't solve the issue) i discovered that the engine control module relay was the fix... 10 bucks. not had a problem since... good luck man

 

[Rosie]

hi guys, sorry for not getting back sooner, was gone for a long weekend. i will try the relay today but do you think a bad relay would cause the truck to only fire on 4 cylinders? i thought a relay either worked or it didn't and if it was bad it wouldn't fire at all???

thanks again

 

[Rosie]

ok so i tired an icm from a good running truck, no change. swapped relays, no change....

so to go over everything so far.

truck starts but won't idle on its own, and cylinders 1 and 5 are not firing at all.

new coil pack, new plugs, tested plug wires, changed out icm, found 2 SPOUTS and they tested fine, tested all wiring for shorts between the coil pack and icm. cleaned all grounds from engine to body and chassis. cleaned MAF, new fuel filter, swapped around relays, new alternator, replaced a bad vacuum line,

thanks

 

[gearheadjlm]

Possible bad injectors?

Try to check the voltage, or swap the injector itself and see if them codes change, just an idea...

 

[modelageek]

Possible bad injectors?

this thread is lost anyways, however he is claiming the 1 and 5 are not firing and you are saying it is bad injectors.........