1994 Transport 3.8 Injector Circuit Dead

[mobby]

Vehicle has great fuel pressure 47lb, has good spark. I cant get any of the injector to work, I changed ECM and crankshaft sensor and camshaft sensor, igition module. If i spray ether in the thrulttle body it will run for a second or 2. I need to know if there is a way to easliy check the inector circuit for a break in the grounds or whichever wires makes those injector work.

HELP!! I'm at wits end now this has been going on for 2 months.

mobby

[LMP]

THis diagram
www.avigex.ca/xport/fuelinjectors.jpg
shows injectors are tied between 12V supply and are grounded through the ECM. YOu have spark so inj fuse is OK....
I suppose you hear fuel pump whine when turning the key to ON.
AN ..unlikely.. possibility would be a corroded splice at S-121..said to be 3 inches from the generator on engine wiring harness. I'd check for 12V on the hot side of any of the injector connectors. Use a test lamp ..just chcking for 12V with a voltmeter would show 12v even is a highly resistive connection was existing through corrosion. A lamp needs current so it will light up only with a good contact.

Is CEL on? Any code retrieved?

[Paul Taylor]

I had a problem a month ago with none of my injectors Firing also.
Plenty of spark but no fuel.

The whole ECU circuit is earthed via the Metal plate that the Ignition Module and Coils bolt onto.
If you remove your coils you will find that under the Ignition module there is alot of corrosion on the ignition module and on the plate.

Clean up these parts and also feed a nice new Earth from the Battery to this large metal plate using some quality wire.
I did this and mine fired right up.

Good luck

Paul Taylor. UK

[mobby]

Ok, I will check the grounding for that under the plate... I had codes for camshaft sensor showing so I changed it and the crankshaft sensor. I dont know of any new codes becuase the engine will not run now.

The problem started with a fuel pump going bad 3 times, so we finally got a good one. The van at least ran then. So then went ahead and replaced crankshaft sensor and camshaft sensor, ign module, had auto parts store check coil packs they are good. Seems something happened during all that work that made it not run at all now.

any other idea's.. Where can I find all those wireing diagrams I see you guy have for the transports? I need the free kind.. hehe

Thanks

[LMP]

I have scanned a lot of diagrams from my 1993 GM shop manual..in most areas representative of 1990-1996 series. There are some offered on E-bay from time to time. I have also collected several scans from other forum members who offer to e-mail the info they have too.
ALl I have scanned and collected at this time is available for download here:
www.avigex.ca/xport/index.txt
..you will have to sort through....
SOme free info sites have been suggested by forum members but I have not kept the list...should have..

[nicke66]

Originally Posted by mobby

... Where can I find all those wireing diagrams I see you guy have for the transports? I need the free kind.. hehe

Thanks

If you want something for free, you have to look outside US. Some friend in Russia gives you the diagrams for year 1997:

http://www.autolib.diakom.ru/CAR/Pon...NG%20DIAGRAMS/

Alldata 8.0 with GM data has been (and still is?) possible to download from the net with bittorrent. What I know, all diagrams are included.

[mobby]

Ok, thanks

Any other idea's what may be wrong with this Van? I need all the input i can get..

Thanks again

[maxwedge]

Originally Posted by nicke66

If you want something for free, you have to look outside US. Some friend in Russia gives you the diagrams for year 1997:

http://www.autolib.diakom.ru/CAR/Pon...NG%20DIAGRAMS/

Alldata 8.0 with GM data has been (and still is?) possible to download from the net with bittorrent. What I know, all diagrams are included.

Try autozone.com/repairinfo, some basic diagrams there.

[mobby]

Well, Im not sure what happened, but it will at least start after i crank it for 30 seconds or more, but it misses and skips and wont idle, and also the check engine light goes on and off and all the gauges start acting really wierd liike moving erraticaly. Oh, and it will not run at 4000 or more RPMS for a moment it started to run normally then it went back to doing same stuff.

What now?

Help



mobby

[mobby]

Could this possibly be the fuel filter? Iwent and checked the little fitting that you connect a pressure gauge to and just a kittle gas come out for a split second then that was it, nothing else. Should gas spray out of that test hole when i press on it?

mobby

[LMP]

Originally Posted by mobby

Should gas spray out of that test hole when i press on it?
mobby

Well not continuously if engine is not running. Engine has to run to keep the pump ON..except for 2 seconds whe turning the key to ON. For a pressure test you can bypass the fuel pump relay.
THe fuel regulator release valve is possibly stuck open...(returns all fuel back to tank).....may be a cLogged fuel filter as you suggest ( always pointed as the culprit but sometimes they are..but this is not expensive and part of a normal maintenance anyway).

[mobby]

I just checked again and on the test circuit the pump runs at 41lbs pressure and it does not leak off so thats a plus i guess. Today i had it running for 3 minutes and it ran good then started acting up again. Also whebi do have it running either running good or like crap If i turn key off it will hardly even start again.

Its like an electrical issue or something, cuz when i rev it it will skip and the gauges act wierd and plus the CEL will flash in sync with the missing of the cyclinders.

wierd
HELP

Mobby

[LMP]

I would seriously investigate a ground problem. CHeck all main connectors, from battery to engine, between body and engine. Run new ground wires between body/engine/battery to be sure . ALso check for the main 12V connector near the power brake and tighten the nut.

[mobby]

Originally Posted by LMP

I would seriously investigate a ground problem. CHeck all main connectors, from battery to engine, between body and engine. Run new ground wires between body/engine/battery to be sure . ALso check for the main 12V connector near the power brake and tighten the nut.

Power Brake? whats that?

Thanks

[LMP]

THE vacuum brake booster..behind the ABS system. The 12V main distribution post is covered with a red plastic cap near the firewall,