NEW INFO! Problem with fuel injectors! Please HELP!!

teedoff00

14 psi boost
Dec 5, 2007
297
0
16
Selah, WA
:1zhelp: So I am doing a 1986.5 7mge swap into a 87 Turbo Shell and I got everything all installed and ready to start and the car cranks but will not start.
Things I have checked and/or tried per TSRM:
1. Checked for spark (+)
2. Checked timing (+ everything was aligned properly)
4. Checked continuity at the MAF plug (+)
3. Checked fuel pressure in rail (+) (didn't check actual pressure because I don't have a gauge, autozone/checker don't have one with a banjo fitting!)
4. Checked spark plug (- plug was dry as a bone!)
5. Checked the fuses (+)
6. Inspected relays (+)
7. Checked for voltage at ecu for the injector wires (+)
8. Checked for voltage at injector clips (+)

What else could be the cause of my injectors not firing? Is it possible that all 6 could be clogged as the car doesn't even sputter? I plan on changing the fuel filter and the spark plugs as a last resort tomorrow. What else could it possibly be? Please help, I need to get this car on the road!
Thanks in advance!
 
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teedoff00

14 psi boost
Dec 5, 2007
297
0
16
Selah, WA
AJ'S 88NA;1090920 said:
Are you using the GE ECU, or the Turbo ECU?

I haven't checked voltage at the injectors yet. I didn't know which of the two wire to put my positive lead on and which to ground to?:3d_frown:
I am using the GE ecu that is the original from the engine.

What should I try if there is voltage at the injectors which I would guess there isn't because the are not firing, so what would I do to fix that.

Thanks for the replies!
 

teedoff00

14 psi boost
Dec 5, 2007
297
0
16
Selah, WA
Poodles;1090952 said:
Are you using the GE injectors, or the GTE injectors?

The GE 380cc (i think thats the size?). Basically, since a little background may help... I purchased a 87 Turbo towards the end of 2006 and used the motor to swap into my 1986.5. Since the body of 87 was rough but the interior was near perfect I decided to fix it instead of crushing it. So I swapped in the 7mge from my '86. As far as I know I have put back in everything that is needed, there are three connectors that come from the drivers side fender wall on the 87 Turbo shell that have no plugs for on the N/A harness/ECU. I think they were for the factory boost gauge, etc. So the 7mge engine is completely stock with only new seals, belts, hoses, clutch, fluids etc. I haven't really touched anything else.
So I am just not sure why the bugger wont start, i dont get why the injectors aren't firing!
Please help with any and all suggestions, because often the only way I figure it out is through suggestions and talking it out!
Thanks again,
 

ForcedTorque

Join the 92 Owners Group
Jul 11, 2005
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Satsuma, Alabama, United States
teedoff00;1091051 said:
The GE 380cc (i think thats the size?). Basically, since a little background may help... I purchased a 87 Turbo towards the end of 2006 and used the motor to swap into my 1986.5. Since the body of 87 was rough but the interior was near perfect I decided to fix it instead of crushing it. So I swapped in the 7mge from my '86. As far as I know I have put back in everything that is needed, there are three connectors that come from the drivers side fender wall on the 87 Turbo shell that have no plugs for on the N/A harness/ECU. I think they were for the factory boost gauge, etc. So the 7mge engine is completely stock with only new seals, belts, hoses, clutch, fluids etc. I haven't really touched anything else.
So I am just not sure why the bugger wont start, i dont get why the injectors aren't firing!
Please help with any and all suggestions, because often the only way I figure it out is through suggestions and talking it out!
Thanks again,

You mention plugs missing, and one possibly being for the factory boost gauge. The turbo pressure sensor is attached to a fuel pump resistor on the driver's side. If that is missing, you may have found your problem. It is a small silver rectangle part with ribbed side on top of the shock tower. I'll return with a picture when I get time.
 
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CRE

7M-GE + MAFT Pro + T = :D
Oct 24, 2005
3,485
0
0
Denver, CO
Per the TSRM the stock injectors should average about 280cc/min. No less than 276cc and no more than 340cc. If it makes you all feel better, the most commonly posted number I've seen is about ~290, not too optimistic but still plenty of room for all of you who just NEED for them to be bigger.
 

teedoff00

14 psi boost
Dec 5, 2007
297
0
16
Selah, WA
Well I did a Walbro "upgrade" just because the factory pump had 136, xxx miles on it so I also did the 12v mod. The resistors are in place on the drivers side. All the connectors on the factory engine harness are plugged up just not a couple that come from the body harness of the turbo shell. As to the injectors I am not sure that the size matters, I just know they aren't firing because the plugs are dry and I have cranked for quite some time to no avail. Any ideas as to what could be causing my problem? There is fuel in the rail (fuel filter, fuel pump are working fine) the problem is those damn injectors...
Thanks guys!
 

CRE

7M-GE + MAFT Pro + T = :D
Oct 24, 2005
3,485
0
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Denver, CO
The 12v mod is only needed for the FEW members on this site who are putting down massive power and the 10th of a second it takes for the relay to throw become downright hazardous. Recheck your wiring there.

So there's fuel in the fuel rail? What's the pressure? Fuel in the rail only means the pump was on long enough to move *some* fuel. Doesn't guarantee that it's even giving you enough pressure to make the injectors drool.

How did you test the fuel pump?
 

teedoff00

14 psi boost
Dec 5, 2007
297
0
16
Selah, WA
Ok, I tested the fuel pump by linking the fp and b+ in the diagnostic box. I know there is pressure because I loosened the cold start injector and it had pressure. I need to check actual psi as I guess incorrect pressure or not enough could cause the injectors to not open. If the pressure is adequate, because I believe it is, what could it be then?
Thanks again for the help CRE, you have given me a lot to think about!
 

CRE

7M-GE + MAFT Pro + T = :D
Oct 24, 2005
3,485
0
0
Denver, CO
Test the injectors and post the impedance of them. Let's make sure you didn't swap in high impedance injectors. I presume they're the ones that were in the 86.5 though?

Then test the +12v line that runs to the injectors when the ignition is in the on position (already mentioned this, have you checked it?).

So you are getting spark and the Check Engine light comes on before you crank the ignition?

Gotta say, I'm feeling baffled... get back on those and we'll go from there. Did you completely swap wire harnesses?
 

CRE

7M-GE + MAFT Pro + T = :D
Oct 24, 2005
3,485
0
0
Denver, CO
Yup, I missed that. As of when do you presume anything to have been done right though? :icon_razz

So, JJ, while you're here.... what's this guy need to be checking?
 

teedoff00

14 psi boost
Dec 5, 2007
297
0
16
Selah, WA
Yeah I did test from E2 to 10, 20 and #30 on the ECU like the TSRM states (could have confused the numbers now since the TSRM isn't in front of me but I know I did it right and got about 12.5 V or so on all three leads.) So from my understanding those three supply power to all six injectors. This is why I am not sure what is up with them not firing. It throws no codes, everything is normal, injectors are the originals, I didn't change anything but the shell the motor is going into. As far as I know everything is hooked up. So what could cause this electrically, since mechanically I think it is in order?
 

teedoff00

14 psi boost
Dec 5, 2007
297
0
16
Selah, WA
So I am changing the fuel filter and the spark plugs tomorrow as a last resort. I have checked all that I can think of from the TSRM. Is there anything that isn't mentioned in the first post I could have missed?
Please Help!:1zhelp:
Thanks for all the info!
 

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
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Redacted per Title 18 USC Section 798
CRE;1092966 said:
So, JJ, while you're here.... what's this guy need to be checking?

Maybe I missed it but two pages of posts and nobody mentions codes?

teedoff00;1093047 said:
Yeah I did test from E2 to 10, 20 and #30 on the ECU like the TSRM states (could have confused the numbers now since the TSRM isn't in front of me but I know I did it right and got about 12.5 V or so on all three leads.) So from my understanding those three supply power to all six injectors.

Your understanding is incorrect. All that proved is the 12 supply, wiring, and injector coils are good. Since the ECU sinks the injectors it doesn't prove anything else. Not to mention for checking that the method you used for measuring was useless.
 

CRE

7M-GE + MAFT Pro + T = :D
Oct 24, 2005
3,485
0
0
Denver, CO
teedoff00;1093047 said:
It throws no codes,


Heh, of course it was only two posts before you mentioned it. :D


That's the problem with walking in and specifying what you know the problem is and then asking how to fix it... most people throw the rest out the window presuming you've had the foresight to check them properly.
 

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
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Redacted per Title 18 USC Section 798
Touche ;)

Yeah, I see now this is a swap. No wonder it doesn't work. And yeah again, I never believe people when they say they "checked" this or that and it's good. I have no idea if they did it right. In fact my experience is they almost always do it wrong, especially if it involves electrics...