Fires but does not run

[Suprabeast4x4]

I swapped a 91 7mgte in to my truck so this complicates the problem but...
I have been reading for days and can't find the answer so we are here.
My fuel system is a 20 gallon fuel cell with and msd efi pump and 8-an lines. the pump is wired to a relay that is switched from ign.

It has spark and fuel because it starts but only runs for maybe a second then dies. I know it is dropping spark but i don't know why. Ecu not getting a signal it want or something.
any help or ideas will be great. and thanks guys

 

[D.J.T.]

Do you have your timing correct?

 

[Volvospy]

Sounds like you have problems with timing for sure. Check timing and the camshaft position sensor make sure it sits right.

 

[Enraged]

check for codes.

if it actually runs, then dies, its probably something to do with the AFM. if it wont even run right, it's likely the timing, either your base timing is off, your cams aren't aligned, or the CPS is off by a tooth.

 

[Devin LeBlanc]

Yep, Double check cam timing, Double check ignition Timing. If you are running a stock ECU and wiring harness without an SAFC you should be able to unplug the AFM and the car should idle just fine.. Any CEL?

Sounds like CPS is out of adjustment

 

[SRZMK3]

that sounds exactly like what my car did when my afm had a wiring problem by the plug. unplug the afm and check if the terminals in the connector are solid also have someone start it and then try jiggling the connector to try to solve it.

 

[Suprabeast4x4]

All the timing and CPS are right where they were when I bought the motor in running order a few years ago (projects are expensive and so a girlfriends haha).
I had a friend and one hell of a mechanic come over after work today and the CPS failed the OHM test it was open in all three terminals. So I need to take a look in inside the CPS and clean if helpful or replace with new. Does anyone have a good source, like cheaper than retail for a CPS. Money is tight but I want the project to f ing run you know.
I won't have time to work on it till sunday so I'll know more then.

Thanks for the help guys. When it runs I'll post a Supra Truck video with burn off and craziness. )
I have a thread in members rides under suprabeast4x4.

 

[Devin LeBlanc]

Check the forsale section, normally they sell 50-100.00 used

 

[jetjock]

Either you're giving us bad information or your friend isn't half the mechanic you think he is. I suspect the second...

 

[3p141592654]

A bad CPS will set a code 12 or 13 and will not start.

 

[Bruno Molly]

was working on a V6 4Runner that was doing the same thing. Good Fuel pressure, good spark, would only Cough like it was wanting to start. Turned out to be fouled plugs from old gasoline since the truck sat for a couple of years..changed the plugs and was roadworthy after that. Cranked right up!..Check your plugs..

 

[Suprabeast4x4]

ITS ALIVE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

The resister for the injectors was missing from the harness. I knew it was something stupid.
It is running a little rough but I drove it around a bit last night. Its a nasty Beast!!!!!!!!!!

so I just jumped and powered up the injectors because I don't have the resister plug (right by the diagnostic plug.) Does anybody know if that resister does anything but just distribut 12 volt or does it reduce voltage I don't think if does but I am not the expert here so.....

Thanks for your help and input. ;-))))

THE BEAST IS ALIVE!!!!!!!!!!!!!!

 

[Dan_Gyoba]

Yeah, no CPS, no ignition.

This really sounds like AFM to me.

 

[jetjock]

...so I just jumped and powered up the injectors because I don't have the resister plug ....

So you bypassed the resistor? Let us know how that works out...

 

[3p141592654]

Its an interesting experiment. I wonder how long the injectors will last with the resistors bypassed.

 

[Suprabeast4x4]

I have at least a hundred miles on it now and it seems fine. I love the torque and the power of this motor. My truck is wicked now. I am so glad to have my project back on the road!!

So is that resistor changing the voltage to the injector or just distributing power? I think it would have killed it by now if it was too much.

 

[jetjock]

It limits current to each injector pair. Required since stock GTE injectors are low impedance. Unless yours have been changed to something else their time is coming...

 

[Suprabeast4x4]

Does anyone have a resistor I can buy. Toyota discontinued them. I'll be checking with local junk yard's this week but I thought that somebody must have part car with one.
I'd really like to get it all dialed in sooner than later.