Jeep no starty starty

[bonza]

stick it on a battery charger and see if it starts after charging up, or buy a new battery.

how old is the battery anyway?

[Jimmyb]

Ok bought new battery, still no go.

My mate Leon, well his bike is now a no go, very fubar! As for him, nothing broken jus very sore, guess that happens when a Hilux drives over the middle of you.

So TJ still no good, actually had hope in the back of my mind with the new battery..... I am outta options again......

[bonza]

try this

http://www.allpar.com/fix/nostart.html

[tassiecj6]

been towed home, now on the street ni front of house if someone wants to burn it.[/QUOTE]

swap ya a CJ6 for it !!!

[Jimmyb]

Thanks Bonza, tried most of those things. Even the map sensor was replaced when i replaced the whole throttle.

[Jeeps]

I reckon the ECU might need re-building. Do you know it's history? When they pulled the ecu apart that i had fixed a few weeks ago they said the capacitors, solder joints and most of the internals were rusty, corroded and falling apart which was common a few years after a vehicle has been flooded.

[Jimmyb]

Well I ended up getting a loaner ECU from Jeeparts in HB. Still no go.....

[bonza]

here is an interesting post I read on another forum some time ago.

may or may not be relevant to you

Oil pump fixed cold hard start

1997 TJ, 4.0, auto, 138,000 miles.

My Jeep ran great until about three weeks ago. I started getting the dreaded code 43 (misfire). The Jeep would idle rough and the oil pressure was dipping low. I wasn't too concerned about the oil gauge reading. We all know those sending units suck. Then again, maybe not.

So I changed:
distributor cap $12
rotor $8
wires $20
plugs $10
Cleared codes by unplugging the battery.
No change in idle. Code 43 came back.

Had the codes read at AutoZone. I was getting a Cylinder #1 misfire and random misfires.
Next day:
changed fuel injector #1 ($5
cleaned all the other injectors and the fuel rail.
Cleared codes by unplugging the battery.
No change in idle. Code 43 came back.

I drove the Jeep for about three days like this. No problems, just a rough idle. I read through countless searches on this board and others. Then the Check Engine light went out and the Jeep started running great again. This lasted for about a week. Then the Check engine light came back on and at the same time the oil pressure would drop to zero, at idle. I would just rev the engine a little to get the pressure back up. No big deal, I thought, the sending unit must be going out.

The following day, I started the Jeep and it idled rough. The oil pressure gauge also showed 80psi! Damn gauge! I went to the parts store, in a different car, and bought a new one. After a quick install, I started the Jeep and tried to rev past the bad idle, but it wouldn't go above 2,000rpm. Then the oil filter seal let go and oil went everywhere. Old gauge must have been working. After cleaning up the driveway, I went and bought some more oil and a couple of filters. I put the new filter on and added oil. This time I started the jeep and let it rough idle for about 10 min. When the engine got up to 210 degrees, the idle smoothed out and the oil pressure dropped. The jeep ran ok, but was showing TPS and IAC codes. The misfire code was gone.

Changed:
Throttle positioning Sensor $48
Idle Air Controller $35 (Pep-Boys)

Cleaned:
MAP sensor and
Ambient Air Temp Sensor
Reset computer and the TPS and IAC codes didn't come back. Jeep still ran like crap. The Misfire code (43) came back after 35 miles. I drove the Jeep like this for a few days. I would let it warm up until operating temp, then head out.

I did a fuel pressure test and it was ok. I hooked a mechanical oil pressure gauge up and it read off the charts when the engine was cold, normal when hot.
I could not figure out how the oil pressure and idle were coming together. The only thing I could think of was the Distributor, because it turns the oil pump. I took off the distributor. The stator and pick-up coil were corroded. Too many trips in the mud. One of the Cap bolt holes was cracked. So off to Auto zone I went.

Replaced:
Distributor $56
Distributor cap $12 (again)

The jeep was still warm, but ran so much better. I had to let it cool completely to test the cold start problem. On the way home, I decided I might as well replace the Ambient Air Temp Sensor as well. What is a few more dollars, right?

Replaced:
Ambient Air Temp Sensor $27
No immediate change.

After letting the engine cool, I started it and still got the rough Idle and high pressure. I decided it was time to try the Oil pump. Maybe it's pressure relief valve wasn't working or something. I ordered a new oil pump and pickup screen from Pep-Boys. It took three days to get it in. While waiting for the pump I had to keep warming the Jeep up every day before driving. The Check Engine light was still on for the misfire code.

Yesterday
Replaced:
Oil Pump $47
Oil Pick-up Screen $27
Rear- Main seal $14 (I was going to be in there anyway)
Oil pan gasket $20 (this one piece design is so much better than the 5 piece on my old 87 XJ)

I also flushed the engine with an engine cleaner. I can't remember the name. It was at AutoZone, in an old style oil can. I had to use a hammer and flat-head screwdriver to puncture the top. I wish I had one of the cool oil can openers. The cleaner smelt like kerosene. I ran it in the engine for 5 minutes before draining the oil and getting to work.

After about five hours of work. The Rear-main seal and Oil pump were in. I need to mention that I hate how Jeep put the exhaust pipe under the oil pan. My XJ's went behind the Bell housing. The old Oil Pump had alot of play in it and didn't rotate very smoothly.

So for the test. Started the Jeep up and had to turn it right off. Forgot to put the two bolts in the exhaust down pipe. Man that was loud. Now for the real test. Started it up and it ran perfect. The idle was normal, the oil pressure was normal and the check engine light was gone. On the test drive the Jeep ran great! This morning I got in the Jeep, started it and drove off with no problems. The performance is better also. It feels like it found the fountain of youth.

The moral of this story is that not everything is as it seems. I searched and read so many things about misfires, cold starts and oil pressure, but none of them ever said anything about the oil pump or high oil pressure causing a bad idle.

I do have one question for the ECU guys. Does the computer have a safety shutoff if the oil pressure gets too high? That is the only thing I could think of.

Hopes this helps someone else.

George



Yes the computer sees the oil pressure. IF not within spec it shuts down the fuel pump