QUICK STORM
B.A.M.F. BMW Tech
Re: idle missfire??
haha, sweet deal. your sy will make high 11s no prob.
haha, sweet deal. your sy will make high 11s no prob.
idle missfire??
- Thread starter gjp
- Start date
UR50SLO
V6+2=LSXCamaro
Re: idle missfire??
Just reading this thread made me exhausted... (no pun intended)
Take that EGR valve off and make a plate to cover it. (it can be temporary)
I've seen countless problems occur on GN's and even daily driver cars with the EGR... Especialy
the problems that come and go. The EGR only comes on at highway speeds and if it's getting
stuck and allowing exhaust in the intake at idle your sure to get a miss. If the plugs that are under
the EGR are going black (back of the engine) it's definatly your villan.
The EGR gets fed exhaust gas at all times when engine is running. If it's slipping exhaust into the
the intake it would become worse when hot (IE) things expand when hot.
Idle the truck and put your fingers on the inside of the EGR valve and pull it open manualy.. see
what I mean about missing!!!!! Make a block off plate! I can snap a picture of my wife's block off plate
if you need one.. I just made it out of allum.
Whew.. at least I've read all the other pages.. and now I can start here LOL.
Scott~
Just reading this thread made me exhausted... (no pun intended)
Take that EGR valve off and make a plate to cover it. (it can be temporary)
I've seen countless problems occur on GN's and even daily driver cars with the EGR... Especialy
the problems that come and go. The EGR only comes on at highway speeds and if it's getting
stuck and allowing exhaust in the intake at idle your sure to get a miss. If the plugs that are under
the EGR are going black (back of the engine) it's definatly your villan.
The EGR gets fed exhaust gas at all times when engine is running. If it's slipping exhaust into the
the intake it would become worse when hot (IE) things expand when hot.
Idle the truck and put your fingers on the inside of the EGR valve and pull it open manualy.. see
what I mean about missing!!!!! Make a block off plate! I can snap a picture of my wife's block off plate
if you need one.. I just made it out of allum.
Whew.. at least I've read all the other pages.. and now I can start here LOL.
Scott~
QUICK STORM
B.A.M.F. BMW Tech
Re: idle missfire??
i told him to try it. but he has phils chip which electronically disables EGR operation, but i could understand it being mechanically defective.
he could get a blockoff plate and then when smog comes around just slap the egr back on.
i told him to try it. but he has phils chip which electronically disables EGR operation, but i could understand it being mechanically defective.
he could get a blockoff plate and then when smog comes around just slap the egr back on.
skwayb
NWSTP
Re: idle missfire??
Mine had the exact same problem. I ended up pulling the distributor and cleaning everything inside it.
Mine had the exact same problem. I ended up pulling the distributor and cleaning everything inside it.
- I replaced the ignition module,
- sanded the spot when it bolted to the Distributor to make sure it was clean
- applied the paste to bottom side of the new ignition module as directed.
- knocked the rust off the star ring and the points on the distributor
- installed a new cap and rotor
- put new plugs on
- Retimed it after the distributor was installed
MRKING
New Parts for Old Trucks
Re: idle missfire??
My idle misfire 2 months ago was just incorrectly set timing and wrong spark plug gap . You should go into this thinking you only have 1k to spend . i am still betting your issue is something small .gjp said:thanks.
My wife gave me the OK to drop 10k into it as I see needed. So I guess I decited to keep it.
gjp
another post whore
Re: idle missfire??
Egr is chip disabled. Just in case I removed it cleaned it and put in on with a new gasket. I removed and capped the vac lines feeding it. Did nothing.
Dist,coil,cap, rotor, wires were all changed. Computer was changed. plugs were changed 5 times with gap first @ .34 and now @ .32
I have checked timming and its good. Have yet to do a tdc test. but why would it miss only when hot. lower fp to 35lbs and missing just about goes away but the dm shows 15* of kr. I think its small problem I overlooked too. I will do heads, turbo & DP, a2a and alky if engine is an easy fix.
Egr is chip disabled. Just in case I removed it cleaned it and put in on with a new gasket. I removed and capped the vac lines feeding it. Did nothing.
Dist,coil,cap, rotor, wires were all changed. Computer was changed. plugs were changed 5 times with gap first @ .34 and now @ .32
I have checked timming and its good. Have yet to do a tdc test. but why would it miss only when hot. lower fp to 35lbs and missing just about goes away but the dm shows 15* of kr. I think its small problem I overlooked too. I will do heads, turbo & DP, a2a and alky if engine is an easy fix.
UR50SLO
V6+2=LSXCamaro
Re: idle missfire??
I realize that the chip does not allow it to come on.
What I'm guessing is inside the EGR the pintle that seats and closes off the exhaust gas from going into the intake is letting some get by it when it warms up. It has exhaust gas pressure and heat going to it when the truck is running. Try to manualy open it with your hand and see if it "misses" like it has been doing. Do it cold when the truck is not missing so you can tell.
All the chip does is not allow the vaccume line going to it to pulse and open.
At least if you put a plate on it you can take out your dist. easier and get to your FPR! Lol..
Good luck,
Scott~
I realize that the chip does not allow it to come on.
What I'm guessing is inside the EGR the pintle that seats and closes off the exhaust gas from going into the intake is letting some get by it when it warms up. It has exhaust gas pressure and heat going to it when the truck is running. Try to manualy open it with your hand and see if it "misses" like it has been doing. Do it cold when the truck is not missing so you can tell.
All the chip does is not allow the vaccume line going to it to pulse and open.
At least if you put a plate on it you can take out your dist. easier and get to your FPR! Lol..
Good luck,
Scott~
gjp
another post whore
Re: idle missfire??
when I push on the EGR it idles bad. Cant get it to miss the same. If I pull an injector it sound like it but at a faster pace. I would guess it would sound like if the injector did not fire once every five cycles. But it is not on any one cyl. Thats why I think it is a ground issue but new grounds did nothing. I will take it in and have it fixed. while its in there I will have some work done. where do I get the blank off plate. I can fab one out of sheetmetal for now if that will work?
when I push on the EGR it idles bad. Cant get it to miss the same. If I pull an injector it sound like it but at a faster pace. I would guess it would sound like if the injector did not fire once every five cycles. But it is not on any one cyl. Thats why I think it is a ground issue but new grounds did nothing. I will take it in and have it fixed. while its in there I will have some work done. where do I get the blank off plate. I can fab one out of sheetmetal for now if that will work?
gjp
another post whore
Re: idle missfire??
used a peice of 14 guage steel to fab a egr delete plate for now. nothing changed. it ran for 10 min then started to miss. I did tap the 5 relays and wiggled wires around and it looked to help?? not sure if i was just wishing but the missing stopped. I am hot so i came inside where the AC is. What do the 5 relays do.? I wiggled the injector connectors too. I will try again when it misfires again.
used a peice of 14 guage steel to fab a egr delete plate for now. nothing changed. it ran for 10 min then started to miss. I did tap the 5 relays and wiggled wires around and it looked to help?? not sure if i was just wishing but the missing stopped. I am hot so i came inside where the AC is. What do the 5 relays do.? I wiggled the injector connectors too. I will try again when it misfires again.
UR50SLO
V6+2=LSXCamaro
Re: idle missfire??
Well... as with other things It was worth a shot. Frees up some engine bay room too.
Reminds me of the old 2.5L GM engines that would crack the head on the exhast side and would run decent till it warmed up and then miss like hell. But that was on just one cyl. Not all like your describing.
You can't pin point it with pulling injector clips off .. I remember you said that.
This is a strange one. Still missing up to 1500 then it's ok....? Does it "jerk" in 3/4th when the converter locks up? like it's missing then?
Wonder what cured it there for a week or so after it came out of that shop?
~Scott
Well... as with other things It was worth a shot. Frees up some engine bay room too.
Reminds me of the old 2.5L GM engines that would crack the head on the exhast side and would run decent till it warmed up and then miss like hell. But that was on just one cyl. Not all like your describing.
You can't pin point it with pulling injector clips off .. I remember you said that.
This is a strange one. Still missing up to 1500 then it's ok....? Does it "jerk" in 3/4th when the converter locks up? like it's missing then?
Wonder what cured it there for a week or so after it came out of that shop?
~Scott
gjp
another post whore
Re: idle missfire??
The guy in the shop turned down the Fuel pressure. It runs good @ 36psi but it runs to lean and I see KR.
Have not yet tried the gasket. I just dont want to do all that work to be shot down again. Most of what I have done (dist,coil,regulator...) were stuff that would need replacing anyways.
Because of the startup smoke and I wanting to add some more HP I will do a l35 head swap and see if the shop can figure it out. I cant think of anything external that would cause the problem. I am sure in time I will fink the problem.
The guy in the shop turned down the Fuel pressure. It runs good @ 36psi but it runs to lean and I see KR.
Have not yet tried the gasket. I just dont want to do all that work to be shot down again. Most of what I have done (dist,coil,regulator...) were stuff that would need replacing anyways.
Because of the startup smoke and I wanting to add some more HP I will do a l35 head swap and see if the shop can figure it out. I cant think of anything external that would cause the problem. I am sure in time I will fink the problem.
![Quickstop [UK]](/forums/data/avatars/m/5/5165.jpg?1570199786){kind=avatar}
Quickstop [UK]
Combating adversyty.
Re: idle missfire??
How is it going? Hope it is coming together.
Mark
How is it going? Hope it is coming together.
Mark
gjp
another post whore
Re: idle missfire??
Unless the truck get real hot the missing is ok. I still have a weird tach flutter that comes and goes sometimes. the rps will drop and raise up 200-300rpm. You can hear the engine too so I know its not just the tach doing it. When I apply te brakes while still on the gas the tack jumps and the bouncing will stop for a while but come back. Then I heard the infamous "dead duck" call. I search and found out its the cheack valve on the Booster. So I bought the RPM one and a few other things too. I still have a few more boxes I am waiting on.
Unless the truck get real hot the missing is ok. I still have a weird tach flutter that comes and goes sometimes. the rps will drop and raise up 200-300rpm. You can hear the engine too so I know its not just the tach doing it. When I apply te brakes while still on the gas the tack jumps and the bouncing will stop for a while but come back. Then I heard the infamous "dead duck" call. I search and found out its the cheack valve on the Booster. So I bought the RPM one and a few other things too. I still have a few more boxes I am waiting on.
QUICK STORM
B.A.M.F. BMW Tech
Re: idle missfire??
all that stuff clean enough to put on a white carpet?
all that stuff clean enough to put on a white carpet?
gjp
another post whore
Re: idle missfire??
No Not realy. It still comes back when the engine gets hot. i am in the proccess of changing a bunch of stuff to keep the heat out of the engine. I also found I had a bad brake booster. Not sure if the leaking booster would cause a bad idle but I guess it could. I will update as soon as my truck is back on the road.
No Not realy. It still comes back when the engine gets hot. i am in the proccess of changing a bunch of stuff to keep the heat out of the engine. I also found I had a bad brake booster. Not sure if the leaking booster would cause a bad idle but I guess it could. I will update as soon as my truck is back on the road.
Don W.
Stab it and steer it
Re: idle missfire??
Depending on what was wrong with the booster, bad idle would be the result. What was wrong with it?
I was just wondering, since there's only 3-4 vac ports open to the manifold what would happen if you just blocked them all right at the manifold as a test. Just thinking out loud again.
Depending on what was wrong with the booster, bad idle would be the result. What was wrong with it?
I was just wondering, since there's only 3-4 vac ports open to the manifold what would happen if you just blocked them all right at the manifold as a test. Just thinking out loud again.