My Colt refuses to start

[iamtall77]

I bought this 89 Colt GT from a reliable source a little over a month ago. I've spent numerous days just gather little parts I was missing. Now it's all together and it refuses to start. The engine will not turn over while the fuel pump is running, unless I crank it over and then plug in the fuel pump fuse. It still doesn't start. It is wired with a Walboro 255lph.

The MPI relay seems to be clicking every time. I went ahead and hooked up the SAFC (it was setup for one already) in case some wires were messed up. I did find one ground to the ECU that wasn't hooked up. Still won't start.

Put some fuel in the tank just to make sure there was plenty in there. Still won't start. Definitely have fuel and air. Compression looks good and the plugs smell like fuel. Going to have a friend come over and make sure there's spark. The SAFC won't read RPM while cranking over and neither will the tach. Not sure if it's supposed to. The CAS that was in the car had some bad wires, so I swapped in another one and still doesn't give me anything. I also checked to make sure it wasn't out 180.

I'm not sure where else to look. I've hooked up my Palm and MMCD, but it doesn't give me anything I can use. Is there anything other than CEL codes that will give me any idea what's up? I'm at a loss. I'll see if my friend comes up with anything. I really need this running and in road worthy shape by October 28th so I can drive to SEMA.

[Toybreaker]

You can quick check your original cas by plugging it into the harness, turning the key to the run positon, and spinning it in your hand.

You should hear the pump run/the injectors click/and see sparks from the plug wires. (remove them from the plugs, and lay them accross the valve cover.

If you get no joy, you may have a bad transistor.

Also, check for power at the coils. (It may be as simple as a popped mpi fuse)

Good luck!

[iamtall77]

I do have spark. I'm charging the battery now in case it just doesn't have enough juice to run the fuel pump and starter at the same time. I'll check the CAS and make sure it works and is in the right position. Why wouldn't the engine crank over while the pump was going? This is really frustrating.

[prophecymiller]

Well, if we look at the basics of a running engine, we need air, fuel, spark, and timing...you already have air, fuel, and you say spark...so this means that either your cas has a problem and not giving the spark signal which would mean the timing is missing, or something is wrong with the ignition system so that you aren't getting spark...now the fact that your starter doesn't turn over when the fuel pump is running throws a wrench into the mix...I would test to make sure the starter is getting power under this condition and also check the continuity of the signal wires to the starter and fuel pump??? It sounds like something is cross connected but is more than likely something simple...I know you probably did this, but you could check over all of your fuses.

[iamtall77]

I thought I was getting fuel. Maybe not. I'm getting CEL code 41 for the Injector Circuit. I checked the injectors and the click when voltage is applied. I swapped out the resistor pack and still nothing. What else do I need to check? I still can't figure out the starter issue. It works when it wants to I guess. I've pulled the starter numerous times to check it and other wires. The last place to look is going to be the fuel pump, but that always seems to work.

[D Walker]

Have you checked voltage at the pump?

[drcustom]

I don't understand why you're not cranking with the pump running...sounds like a wiring issue maybe?

As for it not starting, it's possible that the pump isn't seated correctly, and you're not actually building any fuel pressure.

Do you get any tiny sputters or signs of life, or just pure cranking?

[prophecymiller]

Have you checked voltage at the pump?

Yes, I would also get out my trusty multimeter and start testing everything you can.

[iamtall77]

I'm planning to check everything in case I missed something. It has tried to fire a couple times. Probably just some fuel that leaked into the cylinders. I think the starting problem is from having a low battery. Even though it's brand new, it was only putting out 11.8v read on my Palm. I hooked up a battery charger and it turns over without too many issues. It wasn't fully charged when I tried that.

I swapped out to another ECU just to see if that was the case. It doesn't seem to be that either. I'm going to check the wires from the resistor pack to the injectors and see if maybe there's something there. The wiring diagram in the Chilton's manual sucks and only shows one wire to the resistor and then 4 wires to the injectors. I don't know if there is anywhere else I can check. Hopefully I find something soon before I just poor fuel on it and see if the car will catch on fire.

[iamtall77]

I've basically just narrowed it down to the injectors just not firing. There is resistance between the ECU connections and the injector clips. The MPI relay works, but not sure what else to check for there. The resistor seems to be good. The injectors themselves work and have the proper resistance. The thing just won't run.

I turned the fuel pump on and manually pumped fuel through the injectors with 1.5v and the car ran for about 2 seconds. It seems to run if there's fuel in there. However, the injectors just don't seem to work. What other leads can I follow? What else can I check? What are my alternatives to make it run? I really need some help.

[burnett03]

Have you tried pulling the cas out, turning the car to the "on" position and spinning the cas by hand? the injectors should spray and the plugs should fire.

[prophecymiller]

Have you checked the voltage at the fuel pump like Dwalker suggested? I would also check the fuel filter just to make sure it's not plugged. You could also pull the fuel pump assembly out to make sure the draw and exit tube are both connected...What kind of fpr are you using? Is it working properly?

[iamtall77]

I can try the CAS trick to see if the injectors are even firing. I know I have spark now. I can check my voltage at the pump, but I don't have a FPR yet. The car does have a 255lhp pump and Jack suggested the fuel trim may be too far off to start. I'm positive fuel is getting to the injectors. I'll see if maybe there's a leak at the pickup. Is there a way to check if the stock FPR is working. I do have a complete fuel rail I could swap out if needed. Hopefully I'll get this done tomorrow if it's not too cold.

[D Walker]

check for 12volts on one side if the injectors, if you do not have it, theres a serious issue.

[iamtall77]

I thought I was supposed to only get 6v at the injectors due to the resistor. I did check the connections and got about 6v. It was hard to tell because I have a digital volt meter, but there is definitely power to the injectors. I'm going to go ahead and order an AFPR and hope that's the problem. I'll need one anyway, but I really hope this is the issue. I'm just wondering why I would get the CEL code 41 for the injector circuit if there was too much fuel. To get a code don't you need an electrical problem to occur?

[iamtall77]

I swapped out the entire fuel rail, injectors and FPR, but still nothing. I am getting power to the injectors and my logger is reading injector duty and injector pulse. I'm sure those readings just come from the ECU though. If there was a problem in the harness, where should I look? I already checked the wires from the ECU to the injectors (wires 51, 51, 60, 61) and there is resistance through those wires which leads me to believe they are good. I can't seem to find any good wiring diagrams that tell me where the other wires go, where the wires to the resistor come from, or anything that's helpful. I'm really at a loss here.

[D Walker]

have you checked for actula flow through the rail?

[iamtall77]

I have not checked the flow through the rail because I don't have a fuel pressure gauge. I went ahead and ordered one. Hopefully it will be here this week. I don't think it would help, but I reduced the low settings on my SAFC to -20% to see if that would help. I don't think it helps on start up though. I still can't figure out why it's throwing a code for "Injector Circuit." I read through the Mitsu repair manual and it just says "injectors". I swapped injectors, ECUs, checked wiring harnesses, resistor pack etc. Where the hell is this issue coming from? I did notice that the injectors share a power or ground wire with the purge solenoids and I'll check that. But I can swear the injectors are firing.

[D Walker]

In general I follow the following in this sort of situation in the field where I dont have all my cool tools:

>check for fuel flow- meaning I pull the return line and see if any fuel dribbles out WARNING- be careful! if your not careful your engine can combust externally, which is bad.
>If no fuel there I check for fuel at the pump using a bit of hose and a gallon jug- be very careful doing this
> if fuel at the pump but not the rail I then check at the fuel filter, if its clogged replace it, if it has fuel at the pump but not the filter check for kinked/smashed/etc fuel line somewhere
>if fuel at filter and rail entrance but not at outlet the FPR is suspect

>if there is fuel when the return line is disconnected, I then clamp the return line shut with tape-wrapped vice grips to see if the car kicks. If it does the FPR and everything upstream of it is suspect.
>if it doesnt try and kick or run with the line clamped up, I check the fuel filter for blockage, and use a noid light to check for injector pulse. you can find these even at autozone now, and they are cheap- DO NOT EVER EVER TRUST THE IDC readout from a scantool- it is what the ECU THINKS is happening and has little basis in reality for our purposes- you MUST use a noid light or similar device to affirm the injectors are actually recieving the pulse
>if I have fuel, fuel pressure, and inj pulse, spark and air then the following are suspect: Spark plugs are fouled or have been fouled to the point they will not light off the mixture. Low-compression DSM engines are sensitive to this and if you have fouled the plugs heavily they NEED to be replaced- period.

If I have fresh plugs, fuel at the return line, injectors with verified inj pulse, spark, fuel pressure(even "clamped off") and the car still doesnt run there are serious issues somewhere else and will need to be taken to the shop to be diagnosed.

[iamtall77]

I definitely have fuel and at least some fuel pressure. There was plenty of fuel when I swapped out fuel rails and injectors. I'll try the clamping procedure that you mentioned and see if that's the case. I know the plugs are good and the engine has compression. I'll see if I can find a noid light and check the injector harness. I know I have some energy to them, but maybe not enough or out of sequence. I'll get to this as soon as I finish "observing" my high school art class tomorrow morning. I really hope this thing runs soon.

[iamtall77]

Wow! I feel stupid. Turns out I somehow mixed up the connection to the resistor box with the one on the TB. Same plug size, but different color wires. I kept looking at my 91 harnesses I have and they both have multi colored wires from the injectors to the resistor. The 90 style has all red wires. Yes, feel free to pummel me with retard comments.

The car runs, but is in limp mode due to a bad MAF signal. Just another thing I gotta check out. Probably just the wires from the SAFC mixed up or something.

[prophecymiller]

Cool! I figured that it was something simple...the maf signal, I have no idea about other than make sure the plug is seated correctly? Or like you say, it's safc related.