Resolved 2G fuel pump rewire = bad fuel pump?

[mike96]

when i first picked up my eclipse the guy i got it from had an EVO8 fuel pump to go along with the car. after i got the engine rebuilt and running with the factory equipment i had an issue where the car was running critically lean, getting near 20:1. i ended up replacing almost the entire fuel system including the fuel injectors and pump with the EVO8 unit i was given. and the car ran good for about 8 months. i just went through and finished doing the rewire on the EVO8 pump and now the car is back to running in the near 20:1 range....i am starting to think that may be a pump rewire was a little to much for the EVO8 pump, but the weird thing is that i have a fuel pressure gage installed on my car and as far as i can tell i am getting the correct fuel pressure at idle.

has any one else had a problem with the pump going bad after a rewire?

 

[toofast82]

no, i have an evo8 rewired for about 5k miles with no issues

 

[turboglenn]

Ever think of clogged fuel filter? When i first went to e85 it cleaned s much crap out of my tank and lines that there were 3 seperate times my car started going really lean no matter how muhc fuel i increased. Each time the fuel filter was clogged. The third time i went to a fuelab filter with SS element and the last time i had this issue, I cleaned the element and all gone and good behaviour again!

 

[mike96]

I did forget to mention that I did replace the fuel filter when I rebuilt the car and again when it went lean the first time. However I don't think that is the problem.

The last time it started going lean, it just gradually went lean but continued to run. This time it did a couple of little hiccups on the freeway where it would lean out for about 1 - 2 seconds then went back to running fine. The next morning it ran fine for about 20 - 25 minutes and then out of the blue it went piss lean and stayed that way. I shut the car down and messed with it for a bit trying to get it running correctly again after about 15 minutes of D.S.M. and resetting the ECU 3 times I got it running like it should. Made it into work then later about one mile from home, it did it to me again.

Only now I can't get it to run good any more. Also this is the second/third set of injectors in this car. The first set went bad, replaced with stock, then upgraded to Evo8 injectors.

Another question that crossed my mind. Has anyone had the injector resistor pack go bad?

 

[turboglenn]

They do go bad. I have a few spares if you need one. I'm keeping them for when i get an ECU i can flash so that i can test and learn the code on an engine mounted to a stand. BTU i've got 3 IIRC so letting one go wouldn't hurt.. Measure the resistance on each of them from the one commong wire (forget which one) and i'm not sure what the resistance should be, but if they are not all damn near equal that could be the issue.

But honestly it's starting to sound like a bad ECU or a wire that's shorting. this one has me stumped. DO you have a logger you can hook up and see what's going on?

 

[bwhite]

Funny my 1g is doing the exact same thing too. I have never tried a fuel filter though.

 

[mike96]

update with testing As far as I can tell everything is running like it is suppose to
Fuel pressure is rock solid at 42 - 43 psi with FPR vacuum disconnected 37 - 38 connected.
Getting 12+ volts at the pump, un-did rewire temporarily just to see, no change in fuel pressure.
Checked ignition coils ohms, injectors, so far everything within specs.
Switched out the following sensors to see if they made any change, GM MAF no change, switched back to Mitsu MAF no change, back to GM MAF, changed front O2 no change, changed ECU no change.
Neither ECU is giving codes for anything at the moment at all.
Air flow is showing 25 - 30Hz.
When trying to idle O2 is showing in the very low .1V range which is consistent with my wide band showing now in the 20:1 - 25:1 AF range.

At the moment I have the injectors out for inspection but I think I am going to try one more thing, boost leak test, and if I find one, it better be one hell of a leak. After that I guess I am in the market for a new fuel filter and then some new injectors.

Well i haven't done the B.L.T. yet but I did go down and and pick up a fuel filter and put it in. The car ran great once the pump primed, for about 30 seconds, then it went back to running like poop again.

 

[turboglenn]

HAve you tested the battery terminal connections?> I know it's a dumb question but i fixed a friends jeep today that was acting up, wouldn't idle, running lean etc... batt terminals were still loose from when i had him take it off so i could weld on his door hinge he broke off

 

[xlMcMlx DsM]

Are you running the stock FPR? I don't know the specs on the EVO8 fuel pump, but you could be over running the FPR(assuming it's stock) But get that BLT done and see what that yields. Also, are you sure the fuel pump is good?

 

[mike96]

At this point in time I would say that I am 99.9999999% sure the battery terminals are good considering I have had the battery out and in 3 times in the last 2 days and disconnected about 90 times.

As far as the EVO8 pump is concerned it was good up until I finished the rewire. The pump has been in the car and running good now for about 6 months. The wires have been ran from the battery to a relay for a month or so, just never made it from the relay to the pump until this last weekend then this happened.

I am going to do a BLT today after work and see what I find, after that I am going to wire in the external pump my friend gave me just to see if that fixes it. I know it will over run the factory FPR but I am almost at a dead end.

 

[xlMcMlx DsM]

Check the ground for the fuel pump relay, too. Mine was bad when I first did it on my car, and the car ran like crap and died sometimes.

 

[mike96]

Check the ground for the fuel pump relay, too. Mine was bad when I first did it on my car, and the car ran like crap and died sometimes.

ground is good. i did change where i had it, i even took the Dremel to the spot i grounded it to so it was nice and clean...

BLT is ok only one minor leak nothing big enough to cause the car to run super lean....

 

[spectr019]

Any way to verify that the pump is in fact an evo8 pump?

Ben

 

[mike96]

Any way to verify that the pump is in fact an evo8 pump?

Ben

i could check the part# but unfortunatly the tank is full.

 

[DIRQUIN]

If possible, try pinching the return line and see if it still runs lean. You can still have good pressure at idle on a pump but flow my not be able to keep up after you boost, or even just come off idle. Try to restrict the return line, then see about that external pump.

 

[mike96]

If possible, try pinching the return line and see if it still runs lean. You can still have good pressure at idle on a pump but flow my not be able to keep up after you boost, or even just come off idle. Try to restrict the return line, then see about that external pump.

alright i will give it a shot and see what happens. my biggest problem is the car runs ultra lean even at idle.

 

[mike96]

ok, wow, you might be looking at one very confused person.

So there I was, out in the garage "D.S.M." trying to figure out what is wrong with my car. I figure that I already tried pinching off the FPR return line but I may as well try it once more just to see if maybe I mis-read the gauge or something before I switch out the fuel pump. Wife was in the driver seat doing the cranking, first time cranking = cough, stutter, spit, shutter, die. Second time cranking = nothing. Third crank = nothing. Start beating my head against the wall so I took a minute to collect my thoughts, then want to work figuring out why it wont fire.

I pulled the plugs and everything looked OK so I stuck them in the end of the plug wires to see if I was getting good spark and only one plug had a good strong spark, the other plug on that coil was a little weak but still sparked. The other coil was dead, so I switched the wires around to verify a bad coil and the spark stayed with the one coil. Soooo, I dig out my extra coils and went to changing everything out, get it all back together and guess what, car runs great, no lean condition at all.

I have the car all back together now and have started it up 3 times and let it idle for a bit with no problems. So I am going to take the gamble and drive it in to work and see how that goes. Maybe if everything works good I will hit the casinos this weekend while my luck is up.

I would have never guessed that a bad coil would cause an overly lean condition. overly rich yes, but overly lean? Guess you learn something new every day. Wish me luck.

Well, I sure am glad I haven't gone to the casino yet. Back to troubleshooting.

 

[rEclipserGST]

Whats wrong with it now? Im trying to figure out a similar problem with my car, it cranks but doesnt start. I was thinking fuel filter as well. Im getting fuel and spark. But a friend broke a fuel line when installing the Walbro 255 fp. Im guessing air is getting in the lines or something because when cranking the engine over, the pressure drops down. (pressure gauge on the fuel filter) I have a Weapon R AFPR btw and safc with stock 450s.

 

[mike96]

Whats wrong with it now? Im trying to figure out a similar problem with my car, it cranks but doesnt start. I was thinking fuel filter as well. Im getting fuel and spark. But a friend broke a fuel line when installing the Walbro 255 fp. Im guessing air is getting in the lines or something because when cranking the engine over, the pressure drops down. (pressure gauge on the fuel filter) I have a Weapon R AFPR btw and safc with stock 450s.

same, same, went back to running lean. what is your fuel pressure drop to when cranking and do you have the vacuume line disconected from the FPR when you are checking the pressure?

 

[mike96]

OK so I may have gotten it fixed. Give me a couple of days to make sure everything is running right just to be sure.

At the moment I don't know if something I did to the fuel system actually fixed the problem or if in fact what was really wrong was an ignition problem all along.

The last thing I did to the fuel system was pull the injectors, again, and run some injector cleaner through them.

While I had them out I started poking around and found that I had a bad wire going from the ignition transistor to the coil, had 130 something ohms, way to much. Turned out to be a bad splice job I did about 6 month ago. Anyway, I put it all back together and have about 60 miles on the car with no indication that it is running crappy, so hopefully I got it fixed.

 

[mike96]

Resolved I think. End fix ended up being a bad wire from the ECU to the power transistor for the coils.

Not sure how that makes the car run lean but it seems to have worked, car has been running good for a week.

 

[BkzProblem]

thats good to hear....