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Discussion Starter · #5 · (Edited)
I cannot really see what is what, there are three active pins, on the right side, one on top, two on the bottom. I tried the two on the bottom, didnt get no responce. should the key be on when I ground them or should I turn the key on after I ground them ?

Thanks again

I was checking to see if I had the right start wire (12 volts when in the start position), and I had the wires going to the computer by mistake. I had a multimeter hooked up to it, the yellow wire going to the computer, and the neg side of the meter to the battery. Don't understand how I could have fried the computer like this, i mean i understand static discharge, but I figure I was grounded.
 

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Discussion Starter · #7 ·
I get nothing at all from doing this. Here's what happend. I was checking a wire for voltage, on the ignition moduale harness, and plugged it back in and the car would not start back up. I checked the pins to make shure they were not broken or bent. I replaced the computer, that did nothing, it starts with starting fluid, then dies out. I need to check the injectors, but I don't know where the main electrical connector is. The fuel pump comes on, but I havent found a check valve for the fuel rail, so I havent verified the pressure yet. I'm assuming that if, I can verify that the computer is sending a pulse to the injectors, and I have fuel pressure, then someone must of put a hex on me.




Thanks
Allen
 

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cleanalby said:
... it starts with starting fluid, then dies out...
This sounds familiar don't you think, Advance Design? :)

Allen, when you installed your remote start, did you bypass the VATS (Vehicle Anti Theft System)? Without starting fluid, does the car start and run for a second or so and then die?
 

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So your VATS hasn't been messed with? If I read you right, the only things you've done is disconnect the harness at the column, test for voltage and then reconnect th harness, right?

Just to clarify - will your car start and run for 1 second on it's own without starting fluid?

Advance Design helped me a LOT with a VATS and crank sensor problem on a transplanted 3800. From what I understand about the VATS, the key is inserted and the resistance in the pellet is read by the VATS module. I assume that connection is part of the column harness you unplugged. The VATS sends a signal to the ECM and the ECM will run the engine.

From my experience with VATS problems, the ECM will give a priming shot of fuel as the engine is cranked over. The ignition module handles all the spark based on signals from the crank sensor and will fire the engine with that initial fuel supply. If there is no VATS signal , the ECM will not pick up on firing the injectors after that initial fuel shot is burned so the engine will die. That's where I was stuck for a long time. http://gmtuners.com/ can remove the VATS from your PROM for a great price.

Hope that helps. :)
 

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Discussion Starter · #11 ·
It doesn't start at all without starting fluid. Is there a way to check the fuel pressure without disconnecting the fuel rail
. Would you know where the connection is to check the fuel injectors pulse ??

Thanks
Allen
 

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Stinkin_V8 -

Yep, sounds familiar and glad the Fiero is up and running. We were a good team on that issue. Concerned that this ECM will not flash a code 12 and suprised it would start on starting fluid.

Cleanalby -

Is this a 3.8L?

How did you check the wire you described for voltage? Did you probe the terminal with a voltmeter lead? If so the terminal could be over stretched and not making contact with the module pin. The pressure port on the fuel rail would be near the pressure regulator. You must use a proper fuel pressure gauge to check pressure. Don't want any injuries nor thermal events. If you are not sure please seek professional help.
 

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advanced design said:
Stinkin_V8 -

Yep, sounds familiar and glad the Fiero is up and running. We were a good team on that issue. Concerned that this ECM will not flash a code 12 and suprised it would start on starting fluid.
Three weeks on the second motor, incident-free! Almost ready to dump my V8 S-10 and enjoy some cheap driving. :) Many thanks again!

I just assumed that if he's hearing the fuel pump running, then the ECM may not be one of the models that still flashes codes. But I'm in the dark about the Q4.

Cleanalby, I would check the following, in order: Fuel injector and ECM fuses, fuel pressure (Advance Design is right - fuel is dangerous and will be under a lot of pressure inside the fuel rail), and lastly continuity at the injector harness. Tools here include a fuel pressure gauge (one designed for EFI fuel pressures with a schrader connector) and a noid light, both should be available at your local Autozone or whatever and should cost you around $50.

Just an afterthought - does your radio come on when you turn the key on?
 

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Discussion Starter · #17 ·
Hiya,

I have made some progress. with the help of some starting fluid, the started, and after flooring it a bit it started up. It was knocking a bit (almost sounded like a timing issue, perhaps this was something to do with the injectors ??) and a smoked a bit, and ran rough for a minute or so, I'm assuming that this was learning time for the computer. Then the car ran great. I drove it around for a little and parked it. I was very happy until I went out to start it again. I tried and tried, It seemed like it wanted to but no luck. Could this be that the first time, the starting fluid was able to help it along to get enuff fuel flowing ?? The fuse is fine, and the radio does come on. When I put a meter on the fuel pump test connector, it shows voltage when I turn on the key up until the pump kicks off, Is the voltage indicative of the pressure ?? I don't see any place along the fuel rail to check the actual pressure, and looked extensively around the oil separator.
When I check for continuity at the injector harness, do you mean from the computer ?? If I'm shooting starting fluid into the vacuum line that runs from the fuel rail to the intake manifold, does this mean that the injectors are working ?? I checked the voltage for the dark blue(467) and the dark green((468), when I turn the key on they both power up and then drop off to zero, not really sure what this is doing, but it seems normal to me. Am I correct ?? Should I still have to check for continuity at the injector harness ?? BTW, those numbers come from a wiring diagram by ondemand5 I got from the local tech college I attend for my programming degree, very gracious of them to help, and you guys too. I guess my big question is where do I check for fuel pressure ?? I've worked on many a car (went into programming because I think I really broke my back leaning over cars), but I'm talking about before the electronics got so sophisticated !!


one more thing, I found this tube by the fuel pump test connector and wondered if anyone could id it, looks like a vent.
Here is a picture of it. its the horshoe shape tube with a small amount of ryst on the bottom.

http://www.brionanet.com/humility/allen/pics/tube1.JPG

http://www.brionanet.com/humility/allen/pics/tube2.JPG


Thanks so much for all of your input and help
I am very greatful to all of you
Allen
 

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I'm certainly no expert and I'm basing a lot of this off of a couple of similar systems I've worked on. Sounds to me like the ECM wants to make the fuel pump run and the fuel pump may be working, at least intermittently. There may be a problem with the filter, hard to say. I think you'll find a fuel pressure test very informative - it will tell you if you have consistent (and high enough) fuel pressure. The noid light will tell you if the injectors are opening, they usually open too fast to see them on a voltmeter. Sorry to harp on those two points. They will be very useful tools for you and tell you things that regular tools can't. They're a couple of tools I own and am glad I have them, even if I don't use them that often. I don't know how I ever got by without them.

I have no idea where the hookup for the fuel pressure gauge is on that engine. I can't see it in the pics you posted, either.

Good luck, I wish I could be more help. If you lived closer, you could borrow my fuel pressure gauge. :)

Keep us posted.

P.S. I'm a programmer, too, and I really like the level of sophistication on the new stuff! :)
 
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