I have a 2.8 that has not been running correctly. It seems to do fine until it warms up then it loses power and starts missing. I just checked it in the dark and noticed that the manifolds are red and there are sparks jumping from the metal sleeves around the spark plugs to the exhaust manifold. The timing may be off and causing the red manifolds but I dont have access to a timing light. I believe the wires are fairly new, put on just before I bought the car. I am getting the stuff together to do an engine swap so I really dont want to put too much money into it but would like to drive it in the meantime.
Any help would be greatly appreciated. Steve
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11:32 AM
PFF
System Bot
James Bond 007 Member
Posts: 8872 From: California.U.S.A. Registered: Dec 2002
I have looked several times for vacume leaks and found none. I pulled the sheilds off like you said and it doesnt arc anymore but the exhaust is still red. I adjusted the timing a bit and still nothing. I think that I have a bad exhaust valve leaking fuel causing it.
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01:06 PM
JumpStart Member
Posts: 1412 From: Central Florida Registered: Sep 2006
Ok....I took another look at it and found that the IAC was not really tite and also clicking alot when the switch was turned on so I took it off to check it out and the plunger (jet) came out. I saw threads on the shaft and it did seem to screw into a hole down in the IAC so I screwed it in and put it back on. The car wouldnt idle at all then so I took it back out and unsrewed it so it would freeley move in and out and replaced it. It nows idles but it is rough and is running worse. I then checked the exhaust again and they are still red and found more sparks on the coil pack in the small gap here...
any more ideas? I would really like to be able to drive this thing around localy.
Thanks, Steve
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06:03 PM
Kemp3 Member
Posts: 282 From: Carmel Valley CA, USA Registered: Sep 2007
I have the same issue with the heat shields sparking to the exhaust manifolds ....... still haven't figured that one out , tried 2 sets of new wires already :/ the Exhaust I have no experience with that problem , I assume when you say red your meaning Red Hot ?
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09:53 PM
Whuffo Member
Posts: 3000 From: San Jose, CA Registered: Jul 2003
You've got a little work ahead of you. The arcing at the wires and coil is almost always due to bad spark plugs.
Anyway, here's your plan to get the car running well. First, new spark plugs. AC-Delco R42-TS plugs to be precise; gap them to .045 before installing. Next, replace the spark plug wires, distributor cap and rotor. Follow up with a new coil and you should have a good solid ignition system again.
Removing the decklid (two connectors, four bolts) makes getting to the front set of plugs a LOT easier.
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10:27 PM
JumpStart Member
Posts: 1412 From: Central Florida Registered: Sep 2006
I have the same issue with the heat shields sparking to the exhaust manifolds ....... still haven't figured that one out , tried 2 sets of new wires already :/ the Exhaust I have no experience with that problem , I assume when you say red your meaning Red Hot ?
Yes...Red Hot like a cigarette lighter
quote
Originally posted by Whuffo:
You've got a little work ahead of you. The arcing at the wires and coil is almost always due to bad spark plugs.
Removing the decklid (two connectors, four bolts) makes getting to the front set of plugs a LOT easier.
It does have new plugs but the other stuff im not sure of. I do know that a coil pack can be the most problematic PITA because it can work sometimes and sometimes not. Just best to replace it.
Thanks , Steve
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11:08 PM
Oct 6th, 2007
BobadooFunk Member
Posts: 5436 From: Pittsburgh PA Registered: Jun 2003
It does have new plugs but the other stuff im not sure of. I do know that a coil pack can be the most problematic PITA because it can work sometimes and sometimes not. Just best to replace it.
Thanks , Steve
What brand and type plugs do you run?
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12:55 AM
Mr.PBody Member
Posts: 3172 From: Cincinnati, Ohio, USA Registered: Oct 2006
Maybe a few other things to check. Im not sure what the brand of plugs I had bought. I think they were Bosch Platinum. Im still wondering about the IAC right under the TPS.
Thanks Steve
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06:46 AM
PFF
System Bot
James Bond 007 Member
Posts: 8872 From: California.U.S.A. Registered: Dec 2002
Is the car throwing any codes?What does the temperature gage read on the dash,when the exhaust manifolds are red hot?You might try looking at your cat at night and see if it's glowing red too (might be hard to tell,because of the heat shield cover).if the cat is allso glowing red,then your going to have to wait for it to cool,and gut the cat,or remove the 02 scensor, or drill a few holes (befor the plugged cat) so the car can breathe.Sounds like your cat went into nuclear melt down,but I would onley do this recomendation if your cat is glowing hot.
[This message has been edited by James Bond 007 (edited 10-06-2007).]
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10:18 AM
JumpStart Member
Posts: 1412 From: Central Florida Registered: Sep 2006
Havent checked the cat to see if it is glowing yet. I did check the codes several times. It was always 12. Funny thing was that I even unplugged the IAC and tried the codes again and it just kept flashing 12 over and over never stopping. I figured if something was unplugged it should flash the code for that part.
Also I believe that the cat was gutted out before because it has some welding on it in an "H" pattern.
Is there some special way to adjust the IAC? I dont know if the plunger (jet) needs to be screwed in or not. It seems to me that it can be screwed in and out for adjustment.
Steve
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06:03 PM
Kemp3 Member
Posts: 282 From: Carmel Valley CA, USA Registered: Sep 2007
Havent checked the cat to see if it is glowing yet. I did check the codes several times. It was always 12. Funny thing was that I even unplugged the IAC and tried the codes again and it just kept flashing 12 over and over never stopping. I figured if something was unplugged it should flash the code for that part.
Also I believe that the cat was gutted out before because it has some welding on it in an "H" pattern.
Is there some special way to adjust the IAC? I dont know if the plunger (jet) needs to be screwed in or not. It seems to me that it can be screwed in and out for adjustment.
Steve
You shouldn't have to adjust the IAC.Be sure to check and see if the cat is glowing,the H you see on the cat might mean that it was opened and inspected,then rewelded shut.
Well I took off the heatshields and no more spark from there and I also put a new coil pack on today. I do know how to get the timming close but did find a light to borrow and set it at 10 deg BTDC. I let it warm up and took it out for a drive. Checked the exhaust when I got back and if it is still glowing , its nowhere near what it was but the car still starts missing bad after it warms up. I still cant find any vacume leaks.
Edit: I did pull off the IAC again and found that it had screwed itself in a bit ,I am assuming to adjust itself. I also noticed that the Tach is not showing the correct RPM. I dont know how far off it is but just from driving it I can tell its not right. Its reading too high like redlining at 55-60 mph
Well, its getting closer
Steve
[This message has been edited by JumpStart (edited 10-08-2007).]
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02:40 PM
JumpStart Member
Posts: 1412 From: Central Florida Registered: Sep 2006
I just rechecked the timing and noticed that when I give it a little gas, the timing will jump to about 18-20ish deg BTDC and then it will slowly move acording to the engine speed. I have never noticed that before on any car I used a timing light on. That cant be normal. What might cause this? Thanks , Steve
[This message has been edited by JumpStart (edited 10-10-2007).]
On our cars the ECM advances the timing. Only programming the ECM can change the curve. When you set the 10* base timing though, you do it with the ALDL jumpered so that the ECM timing table is taken out of the process. Did you do that?
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06:44 PM
JumpStart Member
Posts: 1412 From: Central Florida Registered: Sep 2006
I am surprised no one has mentioned a plugged converter............ It can cause the red hot exhausts and the spark arcing can be caused by high pressure in the cylinders making it harder for the spark to jump the plug gaps......forcing it to "look" for other paths.
Just my $.02
Scott
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02:21 PM
PFF
System Bot
Lounge Daddy Member
Posts: 265 From: Kingsford, MI Registered: Aug 2002
On our cars the ECM advances the timing. Only programming the ECM can change the curve. When you set the 10* base timing though, you do it with the ALDL jumpered so that the ECM timing table is taken out of the process. Did you do that?
I just tried jumping the ALDL and setting the timing. Doing it this way it was Way off. Now that it is set, it idles at about 3500 with the idle screw all the way out. It sounds like there is a vacume leak but I have tried everything to find it without any luck.
Steve
[This message has been edited by JumpStart (edited 10-10-2007).]