Bad O2?

[LandoAWD]

Alright,here is what is going on:
I put in a new 16g about two weeks ago, only to find that after the swap I was leaking oil pretty badly around the flex section of the oil return line. Replaced that and I stopped burning oil. Here is the problem: I am throwing a CEL that I have not had the time to pull a code off of (planning on this tommorrow). When the CEL is on, I seem to be running on 2 cylenders; hell, I am getting smoked by hondas The RPMs go up when I step on it, as does the boost, but it basically bogs somthing awful. I had the good fortune of having the CEL go off for like an hour night before last, and finally got to feel 17psi on the 16g. One thing I should mention is that in the process of taking stuff apart for the turbo swap, we cut the lines going from the A/F guage that were tapped into the wires coming out of the O2 sensor; also the wires that hook into the sensor look a little charred. Could this cause this big of a problem or do y'all think the problem lies somewhere else? I am gonna replace the O2 sensor tommorrow anyway, but I just wanted some feedback on possible causes to this b/c I'm about to drive this thing into a ditch Any help would be greatly appreciated, and sorry for the long post.

 

[LandoAWD]

Okay...pulled the codes and they are as follows:
13 Intake air temperature sensor
14 Throttle position sensor
21 Engine coolant temperature sensor
25 Barometric pressure sensor

Now I ask...ALL AT ONCE?!?!?!?

Gonna replace the sensors I guess.....and go from there.

 

[NosLaser]

Before changing all those sensors (and trust me, the TPS is a pain to do right) I would check the connections first. You mentioned wires got burned up, so I would look there first. Re-do any wires that don't look kosher, and check the connections at each of the sensors you mentioned, and after doing so, plug whatever diagnostic computer you used back in, and erase all those codes. See if that doesn't cure your problem first. Always do the easy thing first, and have the hard thing to fall back on. Good luck.

Regards,

 

[LandoAWD]

Did the connector thing yesterday and all seems fine...checked grounds while I was at it...those seem fine as well. Another question I have is, could these all be related? Could one set the other off and so forth? Also, what are the chances of the ECU being to blame?

 

[NosLaser]

Hmmm...the only thing I can think of is either you fried an entire wiring harness, or the ECU is acting up on you. I would try deleting the codes on a DRB or whatever diagnostic you used, and work from there.

Good luck.

 

[LandoAWD]

Deleted the codes with the code reader we were using..started the car back up and there they were again...do you know if there is some sort of harness on the engine side that would house all of these connections? The one to the ECU 'looked' okay, so I thought I would ask...

 

[NosLaser]

If my memory serves me correctly I think all of those sensors run off the same harness. Follow the harness backwards from the TPS and check. I really think it's a wiring problem, because it sounds to me that none of those sensors are even getting a reading; like the ECU thinks they aren't even there. It's only because you mentioned the burnt wires that I am suggesting this. When my flywheel exploded on my Laser, I had to build a lot of these harnesses from scratch. It sucked. Trace them back, and inspect it the whole way. If you have a test light, see if you can find a short and/or a lack of power to a specific wire or series of wires. I'm not very good at electronics/wiring but this is where I would start.

Regards,

 

[LandoAWD]

Hey, I know its a newb question, but where exactly is the TPS??

 

[NosLaser]

The TPS is right on the side of the throttle body. It's a larger, black sensor with a plug about an inch long attatched to it. You'll notice also there is a paint mark on the TPS. This is where this sensor becomes finicky. It's calibrated and set at a specific spot; if you move it, you are asking for trouble. You should never have to remove the bolts on this sensor. There is another sensor on the back of the TB that is a single male connector, and I think it has a green wire. I believe this sensor is part of the harness as well. Check it out and see what you find.

Regards,

 

[LandoAWD]

Found this today and it made me think after not finding any problems in the wiring to these sensors:

Common Symptoms of ECM Failure
Often misdiagnosed, ECU failure can show up in many ways, usually making it seem as if one of the other components, in the fuel injection system, is not operating properly.
Multiple codes, or communication trouble is a good hint, lack of spark, no injector pulse, rough idling, check engine light, all are common signs.

It can appear to be a faulty ISC motor, distributor, coil pack, throttle position sensor, crank position sensor, mass air, etc... many times people change these out chasing the problem, only to eventually find they need an ECU.

Failure is sometimes sudden and final, no start, for no apparent reason, or intermittent starting trouble, getting progressively worse until it won't run at all.

Remove the ECU and open it up if you're not sure, check for signs of visible damage, such as burns, corrosion, or water damage.

Sometimes you can tell the ECU is bad by looking at it, so its at least worth a try.

 

[thehyena]

who makes the replacement ECU's or the fixer upper kits?

 

[LandoAWD]

The fix, assuming the board has not been burned, is to solder on new capacitors.

For a new ECU

www.foreignecurepair.com

Damn this is an old thread.

 

[thehyena]

what's the part number for the 4G37's ECU?

 

[LandoAWD]

Pull out your ECU and look. Also, I'm glad my first thread wasn't as noobish as LarryD's

 

[Newlogics]

Originally posted by LandoAWD
Pull out your ECU and look. Also, I'm glad my first thread wasn't as noobish as LarryD's

So did the problem turn out to be the ECU ?
I had a case of electrolyte leakage, but in my case car just refused to start and ECU was simply clicking (reseting) all the time.

 

[LandoAWD]

Sure was.