420a no start....possible fuel system problem

[eclipse0508]

DSM wisemen needed!!!

here is the rundown...on my 95 eclipse gs i was getting a CEL for o2 sensor heater malfunction, so i replaced my front o2 sensor. Car ran smooth for a week or so. Periodically before this every few times i would try to start my car, i wouldnt hear the fuel relay or fuel pump come on. Obviously it wouldnt start. But most of the time, i heard the fuel pump come on and it started fine. Sunday I was coming home from work and all of a sudden my car started running like crap. It was having trouble staying running and would die at ever stop i made. I had to mash the throttle just to get home. It sounded terrible, like the exhaust was sputtering and felt almost no power. Now the car wont start at all. I haven't been cranking on it, because i dont want to flood it more that it prob is. Now i dont hear the fuel pump or fuel pump relay at all. I ohmed out the relay according the my haynes manual and im getting 75 ohms (which is within tolerance). So im guessing the fuel pump is bad, but i dont want to spend the 250 buck on it and not have it be the problem. Any help would be greatly appreciated becasue this is my daily driver and I need my car back!!!

Thanks everyone for their time reading this long a$$ post.


Josh

 

[VelocitàPaola]

Uh oh... (cue Chopin's "Funeral March"). Perhaps this is another case of the dying '95 ECUs? Your symptoms sound like what Josh was experiencing before his ECU took a dive.

Try using a jumper wire to deliver 12V from the battery to the fuel pump. If the fuel pump kicks on, then... well, godspeed to you, sir.

 

[eclipse0508]

damn...thats not good. i just searched for an ecu just in case, and i had no luck at all. i could only find ecu's for the turbo models. is there any way to test the ecu to make sure its bad? any other help would be appreciated. i am going to run 12v to my fuel pump after work, so i have to wait until then.

Thanks

 

[dr1665]

Sounds like the bastard ECU clan strikes again.

If 12VDC to the fuel pump primes it and the relay is good, then I'd say it's a safe bet the ECU shit the bed on you. Sorry, mang.

 

[eclipse0508]

im hoping its not the ECU...but i dont have the best luck. The only test I could do on the relays is ohm them out and they read 75 ohms. But the weird thing is that i get 12v to the fuel pump relay when the key is on, but not off. Now on the MFI relay,i get constant 12v with the key on or off. Does that sound correct to you? Does anyone know of a way to check to make sure the ECU is bad? Plus im having a hell of a time finding a replacement ECU, so any help there would be nice too.

thanks again

 

[4UH8ERS]

Does anyone know of a way to check to make sure the ECU is bad?
thanks again

Because your car is to the point it won't even start. then find someone who has a 95 and swap ECU's with them. If yours fires up then thats your problem you dont even have to borrow it for an extended period of time.

Just find one and rule that out since it is a 95, you dont want to waist money on a bunch of parts.

 

[VelocitàPaola]

If the ECU is your problem, I say get a new one from Satan. They're $255.00 from my dealer, for a remanufactued unit.

 

[dr1665]

If the ECU is your problem, I say get a new one from Satan. They're $255.00 from my dealer, for a remanufactued unit.

Might also try calling up Fentod Dodge in Michigan and asking for the ASOG/2GNT discount. Usually helps a bit.

 

[VelocitàPaola]

Damnit... I always forget about Fenton. Hopefully, I can remember them for when I rebuild the head.

 

[eclipse0508]

i dont know anyone that has a 95, so the ecu swap isnt available for me. is there any other way to make sure its bad before i spend the cash at the dealer?

 

[VelocitàPaola]

You can try using a multimeter to test the pigtails going to the crank and cam position sensors. The primarily black wires (might have a yellow or white stripe) are usually grounds. With the key in the "on" position, at least one of the other wires should give you a constant +5V signal. If the ECU isn't providing that five volt reference signal, it's probably on it's way out.

Terry has more information (and a clearer explanation) about this test...

 

[eclipse0508]

Who is Terry? Where do I find that information?

 

[VelocitàPaola]

Terry = Talon ESI-T

He's on this site from time to time, but you might have better luck catching him on 2GNT.com. I'm sure he'll chime in when he logs on next.

 

[DSMcrazy3]

I tested my Cam position sensor via the method Paul described, and it told me the ECU is bad.

He's on the right track.

Place the negative lead in the middle hole of your CPS plug, now put the positive lead in one of the sides. One should read 5v. The other one should read 9v. If not, your ECU is done.

 

[Streetracer0442]

hey man i am havin the same problems, looks like you have done the same test as me so far, i would aslo check the crankshaft position sensor and make sure ## timing belt and all that is working. i just replace my ecu and still didn't fix nothin, u said u have the haynes repair manuel it should tell u how to test the crank sensor. from my month of research it usually is the ecu or the cam or crank sensors that go out. if your looking for an ecu the cheapest new ones i found were at advance auto parts, rarely u can find them on her for 150 or somethin, well good luck

 

[4UH8ERS]

hey man i am havin the same problems, looks like you have done the same test as me so far, i would aslo check the crankshaft position sensor and make sure ## timing belt and all that is working. i just replace my ecu and still didn't fix nothin, u said u have the haynes repair manuel it should tell u how to test the crank sensor. from my month of research it usually is the ecu or the cam or crank sensors that go out. if your looking for an ecu the cheapest new ones i found were at advance auto parts, rarely u can find them on her for 150 or somethin, well good luck

ohh yes, definately check the crankshaft positioning sensor on 95's they are notorious for taking a crap on you. thats why they don't make them anymore. you have to buy the conversion from the dealership and put in a 97+ sensor.

 

[Streetracer0442]

advance auto parts has the cps sensor for a 95 gs i just got one priced there like 80 bucks or so.

 

[4UH8ERS]

advance auto parts has the cps sensor for a 95 gs i just got one priced there like 80 bucks or so.

80 bucks for an advanced auto parts sensor uhh they can keep that crap!

Point made the conversion kit at the dealership is like $72.00 or $79.00 and its oem.

 

[eclipse0508]

okay guys, well i noticed that the fuel pump never kicks on now? If the camshaft pos sensor or crank angle sensor is bad, would that cause the fuel pump not to come on? Any more help would be great guys.

 

[4UH8ERS]

okay guys, well i noticed that the fuel pump never kicks on now? If the camshaft pos sensor or crank angle sensor is bad, would that cause the fuel pump not to come on? Any more help would be great guys.

Nope, your fuel pump priming itself has nothing to do with your cam and crank sensors.
you need to test the pump itself first to see if it has failed.

 

[eclipse0508]

okay, ill check the pump. i guess i can check and see if 12v is getting to the pump, and if it is, then the pump is bad right? oh yeah, and i took out my rear seats, and there are two plates with connectors that go into the fuel tank. One of them is directly in the middle, and the other is behind the passenger front seat. im not sure which one is the fuel pump. Any ideas?

 

[VelocitàPaola]

Check the wire harness at the fuel pump for +12V. If you're getting the required voltage, you jumper a +12V lead directly from the battery to the grounded fuel pump to see if iut primes. If it does, then you'll know both your wiring, and fuel pump are good.

I'm not so sure about the CKPS/CMPS-fuel pump priming question though. I know the ECU absolutely needs a signal from the CKPS, CMPS, and knock sensors before it'll let the car start. If one of those is bad, your fuel pump may not prime (since it is controlled by the ECU). One the other hand, your whole ECU may be bad, too.

Read this post for more ECU-diagnosing tips...
http://www.dsmtuners.com/forums/showpost.php?p=151008846&postcount=16

 

[eclipse0508]

****update****

okay, i got to the fuel pump and checked for +12v at the connector, and im getting only about .70 volts. So now im lost even more. I ohmed the relays and they are checking 75 ohms, so anyone have any ideas on where to start now?? any help would be appreciated!!!

Thanks

 

[grncivic2001]

im having the same prob in my 97 eclipse i replaced the fuel pump and still does not prime?

 

[eclipse0508]

***update***
alright guys, here is the latest. i hooked up my fuel pump to direct 12v and the pump works fine. I also checked the fuel pump and MPI relays with my multimeter and also hooked them upto the 12v and both are checking good. So I am really leaning towards the ECU being bad, but Im not too sure how to check it. can someone explain what voltages to expect to the cam shaft pos sensor and crankshaft pos sensor?

Thanks...