How to test for faulty injector plug?

[DeadsEvolution1]

Ok so I ohmed out an injector plug and the resistance measured out correctly. Now my problem is that cylinder 2 injector isn't working at all. We start my car pulled off an injector plug one at a time on each cylinder. If we pulled cylinder 1,3 or 4's plug the car would die but if we pulled number 2 the car would stay on just like normall. The car is spuddering like crazy so we pretty much know that it's an injector or a plug or what??

Can someone tell me how to test the plug to make sure it works? Or does the coil control that as well?

 

[DeadsEvolution1]

Ya I don't know how to do that . Switch the injector pins??

Oh steve here is my E-prom Ecu

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[steve]

Is your car an automatic?

 

[DeadsEvolution1]

Is your car an automatic?

No why?? This ECU was in the car when I bought it from someone. It worked for a few months just fine???

 

[steve]

I can't read the software version number off the EPROM but the ECU was from a automatic. If the EPROM says E931 or is custom then it's been converted but if it says E932 or E932A it still has the automatic software.

 

[DeadsEvolution1]

Well it does say E932a, how is it possible that I am running an Automatic Ecu in my car and the car ran fine?

 

[steve]

The differences aren't that extreme. The injector sizes after correction for the fuel pressure diff between an auto and manual are only about 20cc. The biggest difference is in the idle part of the code since the automatic puts a big load on the engine when you shift it into gear.

It just needs the different software.

It still has original capacitors which is part of the reason why it's not working right now and answers the why you have been through two ECUs in a couple of months, you are putting junk ECUs in it.

 

[DeadsEvolution1]

Ya I figured that much about the Junk Ecu's. The problem was that my friend had one lying around tried it out and it worked so I used it and now it died. Is there a difference between running a 90 ECU and a 91? I know the 90 will make the Tach go wild and it won't work but I was thinking of using it as a temporary fix until I get my ECU back from you

 

[steve]

All you have to do to run a 90 ECU in a 91+ car is swap pins 6 and 14 on the ECU harness. You need a 1/16" flat blade jewelers screwdriver (eyeglass screwdriver) to release the retainer lock and you can pop the pins and swap them in a min or so. Directions are in the tech articles.

The tach will work fine. It's when using a later ECU in a 90 car that you have problems.

 

[DeadsEvolution1]

Ok!!!

I just started to car with the CAS advanced on timing with the 90 ECU. Car started and fuel is hitting all cylinders now, but I am mis firing still. I drove it down the street and came right back, the car had no power at all but would drive. So with that in mind do I just need to set ignition timing now to correct the mis fire?
Also tell me if this is correct, at the coil I have from left the right spark plug wires in this order 4123. Is that correct? Thanks for letting me pick your brain about this I feel I am so close to having this new motor running but still need to fix some small problems.

 

[LambdaJoker]

http://www.dsmtuners.com/forums/maintenance-repairs/10465-firing-order-merged-5-7-a.html

 

[DeadsEvolution1]

Well still evening using the timing light putting the car at 10 BTDC on ignition timing it was no help, the car was still mis firing like it has been. So could the coil pack be causing my issue? I have spark, fuel and compression. I ran a compression test while I was out there it came out at 170 across the board. I have new spark plug wires and spark plugs on the car. Tried different ECU's and new CAS.

No help from either at all. I could really use some help

 

[steve]

Now my problem is that cylinder 2 injector isn't working at all.

Ok!!!

I just started to car with the CAS advanced on timing with the 90 ECU. Car started and fuel is hitting all cylinders now, but I am mis firing still.

Well still evening using the timing light putting the car at 10 BTDC on ignition timing it was no help, the car was still mis firing like it has been. So could the coil pack be causing my issue?

So what are you trying to solve now?

You said your problem was cyl 2 injector wasn't working. And you said that it is now once you put the 90 ECU in. Is is the injector working or not? Are you getting a CEL?

Please set the timing to 5* BTDC like it should be but first make sure that the timing mark on the pulley matches the TDC mark on the front cover when cyl 1 is at TDC. This is needed because the harmonic dampener is know for coming apart and the first sign is the timing mark moving.

What is the part number of the ECU your running and did you swap the pins?

 

[DeadsEvolution1]

So what are you trying to solve now?

I am trying to figure out why I am mis firing so badly now. Also to ad to this I looked at all my spark plugs cylinders 1 & 2 are white and on 3 and 4 they are more black.

Is is the injector working or not? Are you getting a CEL?

And the injector was working for a little bit than it just stopped completely again and yes I am getting a CEL. I don't have a logger though so I can't check the code

What is the part number of the ECU your running and did you swap the pins?

ECU: MD166262
E2T36578

No I did not swap the pins, actually I forgot about that actually what does that do for me?

Engine is at 5BTDC now and the timing marks of the pulleys line up still to the front cover

 

[steve]

I am trying to figure out why I am mis firing so badly now. Also to ad to this I looked at all my spark plugs cylinders 1 & 2 are white and on 3 and 4 they are more black.

And the injector was working for a little bit than it just stopped completely again and yes I am getting a CEL. I don't have a logger though so I can't check the code.

ECU: MD166262
E2T36578

No I did not swap the pins, actually I forgot about that actually what does that do for me?

Engine is at 5BTDC now and the timing marks of the pulleys line up still to the front cover

That's a 91/92 Federal MT AWD ECU not a 90 like you said. There should be no need to swap the pins with it.

You need to pull the error code, without a logger you have to do it the old way.
If it's a 41 your back to diagnosing the injector problem. Did we discuss the fact that the injectors can measure fine when cold and open when hot. Are these stock injectors?

 

[DeadsEvolution1]

No we didn't discuss that, and yes they are the stock injectors. I have a new set of 650's laying around with no way to control them yet so I can't put them in. I was reading on the injector clips and how if you mess those up sometimes your injector wires can fail. Well my car never had those clips when I got the car from the previous douche bag owner who blew up a newly rebuilt motor in 50k.

What should I be looking for? Could my transistor pack be bad? Could my coil be bad? Or my wires.

 

[steve]

Not having the retaining clips has caused more than one person to have injector problems.
You can buy new ones from summit pretty cheap and splice then into your harness or see if the existing pins fit into the new connector.

MSD Ignition 2400 - MSD EFI Injector Connectors - Overview - SummitRacing.com

or

Home » Shop » Connectors / Harnesses » Injector connectors » GM Delphi / Packard - Bosch EV1 Type Injector Connector Pigtail Push to seat

 

[DeadsEvolution1]

Well thank you for those links. I just got a new coil and a new transistor pack for my car to try out. My friend gave me the cable to log but it's for PC and my laptop does not have that old 9 pin plug

I found an intersting thing today. So after all I have done,
New coil pack, new cas, new plugs and wires, new ecu, new injectors, compression test, redid timing. set ignition timing to 5btdc, check for fuel and spark. Gosh I have done alot that I can't think of also.

So today I pulled out each injector plug to take a look at the wires and cylinder 3's injector plug wire was so brittle it broke right out. And cylinder 1 and 4 look the exact same way as 3 did!! So I think My wiring was the problem

 

[steve]

Common problem. After 18 years of under the hood heat the insulation gets hard and brittle and the wires break.

 

[DeadsEvolution1]

can anyone tell me where I changed this to resolved?? I found it one time by mistake but now I can't.

So guys I put in new injector plugs and it did not fix my issue. So with that in mind I went ahead and pulled the timing on my car, and pulled the valve cover off to check the lifters. After removing the cams I found 4 Dead lifters 2 on the exhaust and 2 on the intake. So I put in a complete new set of 3G lifters and what do you know. No more misfire nothing it runs smooth. After about 10 minutes the car died and would not start at all. I pulled the spark plugs to check them, cylinders 2 and 3 spark plugs were black and smelled like fuel. So I replaced the coil and now I am happy!!!