Please help - '03 LLB OBW turns over but won't fire

[OB99W]

[...] A little trick I learned (kinda shade tree but it works as long as you're careful) when you have wire that is suspected to be bad between two connectors and you don't want to tear into the harness, splice a new wire of equal gauge in place of the "bad" wire between the two connectors and see if the problem continues.[...]

Yes, that can work, as you said, "as long as you're careful". I'm a bit concerned about doing it at the ECU, since accidentally applying power (or whatever) to the wrong pins can lead to the "magic smoke" escaping.

[Fairtax4me]

Yes, that can work, as you said, "as long as you're careful". I'm a bit concerned about doing it at the ECU, since accidentally applying power (or whatever) to the wrong pins can lead to the "magic smoke" escaping.

 

Yes, 'tis the reason for the disclaimer.

[live2fish]

I noticed the B137 #2 wire had already been cut and spliced back together once before when I started to remove the tape and covering from the ECM connector harness. I also noticed that B137 #2 & #3 appeared to enter the engine compartment through separate harnesses - one yellow/blue (YL) wire to B20 #4 and one YL wire to B22 #10. I "unspliced" B137 #2 and cut B137 #3. Next I tested for and found continuity from the wire harness side of B137 #3 to B47 #4 and also from B137 #3 - B20 #4.

There was no continuity between the previously spliced wire harness side of B137 #2 - B47 #4 nor between B137 #2 - B20 #4; there should be, I think.

 

Next I cut YL wires B47 #4, B20 #4, and B22 #10. I crimped a connector and a jumper wire to each cut wire. The wiring diagram shows that all five of these YL wires are in series so I put a big wire nut on all 5 jumpers and re-ran the "Engine Starting Failure Diagnostics – ECM Power Supply & Ground". The tests all passed and there was now correct voltage at the ECM B137 #2 and B137 #3....

 

...but the car still cranks with no fire!

 

After I run a new #2 YL wire and splice the others it back together I suppose a proper fuel pressure test using a better gauge than my finger and thumb would be next?

 

live2fish

)><(())*>

[Fairtax4me]

I don't have the FSM handy so I can't look to say if the YL wire on B137 2 should have continuity to pins B47, 22 or 20, but generally if there are separate wires to the ECU, it's for a reason.

 

It does have fuel in the tank right?

 

Did you check all the fuses after doing the electrical work?

I'd hope that you disconnected the battery beforehand so the ECU should be cleared.

[OB99W]

May I suggest that before any more cutting/splicing/jumping is done, that you consider another possibility? It's not uncommon for the B20-to-E1, B21-to-E2, and/or B22-to-E3 connectors to develop some corrosion over time, especially where road salt is used in the winter. This can lead to all sorts of problems, since power, ground, sensors, solenoids, etc. all depend on those connections. If you haven't done so already, I'd suggest pulling apart each of those pairs and spraying out the pins with alcohol -- some isopropanol from the drug store works better than electrical contact cleaner, in my experience. If you can see any obvious corrosion, gently scrape any pin showing it. Be sure to thoroughly dry the connectors (a portable hair dryer works well) before reconnecting.

[live2fish]

I don't have the FSM handy so I can't look to say if the YL wire on B137 2 should have continuity to pins B47, 22 or 20, but generally if there are separate wires to the ECU, it's for a reason.

 

It does have fuel in the tank right?

 

Did you check all the fuses after doing the electrical work?

I'd hope that you disconnected the battery beforehand so the ECU should be cleared.

 

Thanks for the suggestions and help. The diagrams E/G(LH6)-03, E/G(LH6)-06, and E/G(LH6)-11 from the "WIRING SYSTEM" section, "ENGINE ELECTRICAL SYSTEM" sub-section show that the wires should be connected electrically - I'm hoping it's correct? Thank you, yes, 5/8 full tank. I did not go back after cutting and splicing to check the fuses again, but I hear the fuel pump running when cranking (back seat still out). I disconnect the negative cable when I mess with the ECM and wiring harnesses. I assume this is part of being careful.

 

Is the magic smoke the smell and sight of burning/melting wire insulation and metal caused sometimes by extreme heat when electrons try to "jump" too far (loose power wires)?

[live2fish]

May I suggest that before any more cutting/splicing/jumping is done, that you consider another possibility? It's not uncommon for the B20-to-E1, B21-to-E2, and/or B22-to-E3 connectors to develop some corrosion over time, especially where road salt is used in the winter. This can lead to all sorts of problems, since power, ground, sensors, solenoids, etc. all depend on those connections. If you haven't done so already, I'd suggest pulling apart each of those pairs and spraying out the pins with alcohol -- some isopropanol from the drug store works better than electrical contact cleaner, in my experience. If you can see any obvious corrosion, gently scrape any pin showing it. Be sure to thoroughly dry the connectors (a portable hair dryer works well) before reconnecting.

 

Thanks for your help! They looked good, but I will try it anyways.

[Cougar]

I have been looking over the posts on this thread and it sounds to me that the injectors aren't turning on for some reason. The ECU controls the ground side of the injectors and makes a connection to ground when they are supposed to be open and inject fuel to the cylinder. Have you checked the voltages at the connections to the ECU for the injectors to see if you have power getting to those points? If so and you have around 11 volts at each connection then we need to see why the ECU isn't closing the connections to ground when they need to be.

[Fairtax4me]

Is the magic smoke the smell and sight of burning/melting wire insulation and metal caused sometimes by extreme heat when electrons try to "jump" too far (loose power wires)?

Yes the magic smoke is what all electronics run on, and if it gets let out they stop working.

 

It's the smoke you get when something electronic overheats and burns out or even catches fire. Very distinct smell. Usually it's caused by a short.

[live2fish]

I have been looking over the posts on this thread and it sounds to me that the injectors aren't turning on for some reason. The ECU controls the ground side of the injectors and makes a connection to ground when they are supposed to be open and inject fuel to the cylinder. Have you checked the voltages at the connections to the ECU for the injectors to see if you have power getting to those points? If so and you have around 11 volts at each connection then we need to see why the ECU isn't closing the connections to ground when they need to be.

 

Thanks for the input. The pink and violet wires between the ECU and each individual injector - B137 #1 (injector 1), B136 #8 (injector 2), B136 #5 (injector 3), B136 #4 (injector 4), B136 #3 (injector 5), and B136 #1 (injector 6) - would have to be the "valve open" signal wires, right? If there is continuity between the ECU connector pins and the injectors and good ground between the ECU and the body, how do you test for the correct "valve open" signal from the ECU to the injectors?

 

As far as I can tell, the main relay B47 pin #4 supplies power directly to the ECU at B137 #2 and #3, B20 #4, and B22 #10 (to injectors). There was power to injectors, but not to the ECU. Inside the wiring harness the relay wire connects to the ECU wires and also to the other wires that feed the two connectors under the hood. There was a disconnect in there somewhere and no power was being supplied to B137 #2 and #3 so I jumpered the power supply as decribed previously and that ended up resolving the power supply to the ECU and power was still supplied to the other connections also.

 

I am reaching the point of diminishing returns here. I have only taken a vehicle to a shop for repairs after knowing what needed to be fixed and deciding I couldn't repair it or didn't want to repair it. I am wary of taking it in without a better idea of what needs to be repaired (whole different control problem).

 

I am going to go through each diagnostic for no start step by step once more. If I can't get it resolved, I will need to place in the hands of capable professionals.

 

Thanks Again for the help.

 

live2fish

)><(())*>

[OB99W]

I understand your concern, but sometimes it's better to have a pro who can actually see and touch things do the work, rather than having us try to direct you "via remote control".

 

You might want to check at least one more thing. Since power on the yellow/blue wires has been an issue, have you verified that it's getting to everything that it should? Specifically, the cam sensor should be powered when the key is "ON" -- check at its connector (E15) pin #1. That wire is (of course ) yellow/blue.

[Fairtax4me]

If there is continuity between the ECU connector pins and the injectors and good ground between the ECU and the body, how do you test for the correct "valve open" signal from the ECU to the injectors?

With a Noid light.

http://www.amazon.com/WILMAR-W85104-FUEL-TEST-LIGHT/dp/B0002KO432/ref=sr_1_10?ie=UTF8&s=automotive&qid=1271974046&sr=1-10

 

You can buy a whole kit for something like $20 at most parts store or get just the one you need for around 5 bucks. Plug it into the injector harness, if it flashes it's getting signal from the ECU. You can check voltage at the harness if you have an Oscope. You might be able to do it with an analog VOM, but you need a very fast reading meter to see the correct voltage. An Oscope (oscilloscope) will show the entire wave form as the ECU pulses.

[Cougar]

The "valve open" signal going to the injectors is really just a connection to ground through the ECU. This happens very fast of course and is a short duration. You would really need a scope to test it. My main concern was that you verify have around 11 volts getting to the ECU pins coming from the injectors if power is getting where it should be when the ignition is ON. You can use a noid light as was suggested to see if the injectors are working but from what you have stated so far it looks like they are not opening.

 

Along with verifing that all pins that supply power to the ECU are getting power also make sure that all the pins that are supposed to tie to ground are making good connection using your meter. A good ground connection point will have no voltage across it when compared to a good ground reference point.

[live2fish]

The injectors all have good ground - tested with a noid light. Cleaned the connectors. Went through the no start diagnosis again and I'm back to the fuel system. Got a good fuel pressure tester and there is only 10 - 15 PSI when cranking and none afterwards. I replaced the fuel pump already. There is no gas in the fuel pressure regulator vacuum hose. Is there some kind of check valve in the gas tank that is not part of the fuel pump?

 

I also got a new code - P0113 - Intake Air temp circuit high input. The car still won't start, so I can't complete the first step of the diagnosis. But the freeze frame data showed 59ºF coolant temp and 55ºF IAT.

 

Please tell me I need a new gas cap. Is that a possiblity? I can hope.

 

Thanks for the help.

 

live2fish

)><(())*>

[OB99W]

Exactly where are you measuring the pressure?

 

A defective FPR doesn't always present as diaphragm leakage into the vacuum side.

 

If you suspect a tank venting issue, you could try cranking with the gas cap removed and see if the fuel pressure increases.

 

When you replaced the fuel pump and filter, did you inspect the old filter to see if there was any debris?

 

Have you verified that full voltage is getting to the pump and that the ground connection there is solid?

[hankosolder2]

If you think it might be the fuel pressure regulator, you can try blocking the return line. (i.e. it 'bleeds off' fuel pressure above the set point back to the tank through the return line...but if it stuck, you would have very low fuel pressure.) With the return plugged, you should have higher than spec fuel pressure- unless something other than the FPR has failed.

 

I guess a vacuum leak on the intake side of the fuel pump could cause this issue, as others have said, check the voltage AT the fuel pump. Perhaps a plugged fuel filter or intake sock if it has one?

 

Nathan

[live2fish]

The pressure gauge is on the passenger side fuel rail line where the damper was located. Voltage is getting to the pump connector and I can hear the pump turn on when I key up the engine. Unfortunately, I did not inspect the fuel assembly fuel filter nor change it, replaced the pump and strainer bag. I pinched closed the fuel return line and the fuel pressure did not increase.

 

Newbie mistake on the tank filter. The original intake sock was pretty dirty. I need to take out the assembly again and check and replace the filter in the tank. I replaced the canister filter under the hood.

 

Fuel pump intake vacuum leak?

 

live2fish

)><(())*>

[live2fish]

Thanks to all of you who helped me find the problem and fix my LLBean.

 

I found and repaired a poor connection inside the loom on the yellow blue power supply wire (a second wire was spliced into the main wire and was barely connected by about 3-4 strands of wire). There are lots of wires!

 

I pulled the fuel pump assembly again to double check for problems. I noticed this time that gas was running out of the bottom of the assembly, not just dripping from the strainer bag. I was checking for a canister filter, which I discovered the 2003 3.0 does not have inside the holder. But, there is a shallow cap with an o-ring on the bottom of an otherwise empty "fuel delivery reservoir".

 

This clue - "vacuum leak on the intake side of the fuel pump" - led me to find the problem on the "discharge side". The o-ring was poking out a little on the side of the canister facing the fuel pump and one of the metal latches on the cap looked "bent". Looking closer, the latch was split about half ways where it bends up from the cap, barely catching the outside edge of the tab on the canister. So, when I tried to start the engine, fuel was leaking back into the tank, preventing the system from pressurizing. I couldn't locate just the cap, so I got the whole assembly from my local dealer who gave me a 20% discount.

 

I installed the new assembly, put everything back together, lots of electrical tape and some rubber pool liner to protect the wiring (yes very dry) and it started right up.

 

How many times have you seen this problem? Add this to the reasons for a "NO START" - faulty in-tank fuel filter canister cap. I was told it was not a serviceable part. I suppose I could have installed the longer metal filter holder (cap) that is used on the 2003 four banger and just left out the filter (mine is under the hood), but I didn't.

 

Thanks again for all the help, it is very much appreciated.

 

live2fish

)><(())*>

 

Two days later, the CEL came back on and....

[Cougar]

Good job on the repair of this issue and thanks for the update.

[OB99W]

Congrats!

Two days later, the CEL came back on and....

 

Or was that premature? :-\

[Fairtax4me]

Glad to hear you got it running. I would suspect that one would rarely see this type of failure, glad you got to be the guinea pig instead of me.

 

Jk, congrats on fixing a very uncommon problem.