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Unread 01-23-2008, 06:36 PM   #16
Alfons
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Quote:
Originally Posted by veritas4156
Heh finally I feel good about myself with regards to my jeep. When I took the cover off I decided if I was gonna do this much work I'm gonna replace the gears and chain

On the other side of the spectrum, I did all the timing stuff(perfectly I believe) and it still doesn't start. If I floor it while cranking then it backfires. And by back fire I mean a plume of FLAMES out the intake. I'm beginning to think I bought a Heap not a Jeep. I'm gonna try changing the computer tomorrow in case the computer is messed up. Unless anyone has any other ideas...
You're almost there. You have the distributor installed one tooth retarded, so when the exhaust valve opens there's still flame in the cylinder & your manifold will start to glow after a short time. Follow the instructions exactly, especially the marking on the distributor housing of where the left side of #1 cylinder distributor cap post is, then when you put the distributor in, the tail of the rotor should be at (or very close to) this point - in other words, at TDC, the rotor should have just gone by #1 post.

If you install the distributor too far advanced, it shouldn't start at all.

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Unread 01-23-2008, 09:33 PM   #17
veritas4156
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the car isn't starting at all and its backfiring out through the throttle body not the exhaust. If the car ran it would be wonderful because I still haven't seen it running since I bought it...
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Unread 01-24-2008, 03:29 AM   #18
Alfons
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Reset the distributor, it's firing but at the wrong time - your ECU is doing it's job.
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Unread 01-24-2008, 03:31 AM   #19
Alfons
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Quote:
Originally Posted by veritas4156
the car isn't starting at all and its backfiring out through the throttle body not the exhaust. If the car ran it would be wonderful because I still haven't seen it running since I bought it...
Reset the distributor, it's firing but at the wrong time - your ECU is doing it's job.
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Unread 01-24-2008, 08:32 AM   #20
veritas4156
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ill be out there working on it all day today, just came in for a minute to get warm. thanks for the thoughts on the ECU. I really didn't want to have to swap it out. How difficult is it really to set the distributor right? I've done it on other cars and never had this much trouble...
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Unread 01-24-2008, 09:56 AM   #21
Alfons
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If you:
  1. set #1 cylinder to TDC with the timing marker at 0 degrees,
  2. mark the position of the left side of the cap #1 post on the distributor case as described,
  3. then align the oil pump slot properly,
  4. slide the distributor in as described, and
  5. check that the tail/backside of the rotor is on or just past the line once the distributor is fully inserted.
the distributor should be good to go. I've gone through this procedure quite a few times & it's easy to get the distributor one tooth off one way or the other, but if you check the rotor positioning, any misalignment is easy to see - you just pull it back up and re-do steps 3,4, & 5. If the distributor is in properly and you still get misfiring, then you'll need to look elsewhere for the problem.
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Unread 01-24-2008, 01:32 PM   #22
veritas4156
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YAY! Thanks everybody, especially alfons, you are now the coolest canadian I know. The jeep runs now, although it is a little rough. I believe it might be the throttle position sensor, but I'll make another post about that. Thanks again guys!
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Unread 01-24-2008, 03:22 PM   #23
Alfons
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You're very welcome & good work Pretty soon you'll understand how all the elements work together to make your jeep run, then you'll be able to pass on your wrenching skills & experience

The TPS can cause a lot of problems that seem to point to other things, good luck.
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Unread 01-29-2008, 03:32 PM   #24
veritas4156
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alright so I believe the timing is right, when I swapped the TPS it didn't change anything. The jeep is still running rough, and it likes to stall out after a few minutes of running and then not start again unless you remove the fuel pump relay. I checked the ignition timing with a gun and apparently its firing about 12 degrees BTDC while running. Could the ignition timing still be off?

Weird thing is that if I start it running and disconnect the fuel pump relay it idles great for about 30 seconds, just cant hit the gas otherwise it will die. The timing remains at 12 degrees BTDC though.

Any ideas?
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Unread 01-29-2008, 08:55 PM   #25
veritas4156
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any help? could it be one tooth off on the distributor? i thought that would make it 28 degrees off or more
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Unread 01-30-2008, 03:29 AM   #26
Alfons
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The description "running rough" doesn't give much information, but off-hand, I'd say that you have a sensor problem - when the engine heats up and the ECU goes into "closed loop" operation, it doesn't appear to like what it sees - ergo "rough running". In a lot of cases, when the TPS is acting up, you'll get the symptoms you're describing, but if that's not it, you have two very wide areas to investigate - fuel & electrical/ignition. I would recommend doing a few more tests, like fuel pressure (with & without vacuum attached) & manifold vacuum. A good description of your engine would help, including what sensors, ignition parts, etc have been changed.
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Unread 01-30-2008, 07:04 AM   #27
laybackman
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Quote:
Originally Posted by veritas4156
any help? could it be one tooth off on the distributor? i thought that would make it 28 degrees off or more
That would be true if timing was controlled by vacuum but your is controlled by your ECM so it is trying to compensate. You are probably one tooth off. If I was to guess the dist shaft position need to be advanced, (rotated clock-wise) one more tooth.. Once you get this engine timed either the rough idle will be gone or you will need to address that issue seperately. It could be a dirty IAC or you need to dump the learned memory in the ECM.
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Unread 01-30-2008, 07:41 AM   #28
Alfons
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Quote:
Originally Posted by laybackman
That would be true if timing was controlled by vacuum but your is controlled by your ECM so it is trying to compensate. You are probably one tooth off. If I was to guess the dist shaft position need to be advanced, (rotated clock-wise) one more tooth.. Once you get this engine timed either the rough idle will be gone or you will need to address that issue seperately. It could be a dirty IAC or you need to dump the learned memory in the ECM.
Laybackman may have a point in that the ECM is trying to compensate as much as it can, but I don't think you want to move the distributor further into the advanced area. With each tooth of the distributor representing approximately 28 degrees (there are 13 teeth on the distributor, and 360 / 13 = 27.69), so if it was moved further in the advanced direction, it would be trying to fire an additional 28 degrees before it's firing now (it's already 12 degrees BTDC, so that would make it 40 degrees BTDC) - I don't think it would start. You may need to "loose some" advance, (go the other way by one tooth) but if you could take a picture or two of your distributor at TDC showing the rotor position and the #1 cylinder mark on the distributor case, that would be helpful. The other points made by laybackman are also good - the whole throttle body could use a cleaning - there's a gallery from the IAC cavity that goes farther down into the throttle body & can get clogged.

BTW, do you know for sure that #1 piston is at TDC or are you just going by the timing mark?
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Unread 01-30-2008, 08:45 AM   #29
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Do you know if this is a stock distrubuter? I had a issue with one I bought at a parts store. I had to get a OE one from the dealership. Also did you check the teeth on the distrubuter to see if they were worn at all?
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Unread 01-30-2008, 08:51 AM   #30
veritas4156
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i was going by the timing mark, i figured that was pretty accurate, though when i set my timing underneath and 99% sure the #1 piston was at TDC (used a pencil to find the highest point) and I put the cover and crank pulley back on it looked like I had set it at 2 degrees BTDC. The throttle body has been cleaned, the IAC has been changed, the TPS sensor has been changed, the MAP sensor has been changed, and the Crank Position Sensor has been changed. By running rough I meant that it sounds like it is missing on a cylinder but all plugs(Bosch Platinum2), wires(Xact), cap and rotor(GPSorenson) have been changed. I'll take pictures later today of the rotor position at TDC.
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