Little diagonosis help please(off idle hesitation)
05-08-2004, 10:09 AM
#1
Little diagonosis help please(off idle hesitation) After installing my heads/cam & getting tuning done ive noticed an off idle hesitation that horribly hinders my 1/4 mile performance...if i smack the throttle off idle the car bogs for id say darn close to a full second...at the track with hoosiers set at 26 psi i bogged producing a wonderful 2.2 second collage of 60's because my converter wasnt able to flash...i went to cartek & they hooked me up to tech2 and noticed in a few frames i was having missfires @ say 20 a pop...i hooked up my autotap and same **** a few on each cylinder @ idle but then youd get like 20-40 in just one frame from a couple of them. Cartek immediatly though wires...ok they were new msd's but i didnt have this hesitation before the heads/cam, but i took their advice and swapped in some new wires but still the same hesitation off idle...i checked my plugs and they seemed to be in good shape they are ngk55's set with the gap they came with...basically it sounds like an ignition issue but why when i get rolling do the missfires go to 0? Could this in anyway be cam related because i know i had set the p0300 code for missfires or is this ignition related because its continuing?
Thanks guys
Bill
ps just added 2 current autotap logs to post one wot run which while @ wot 0 missfires & one misc driving and as you can see the missfires are all over the place.
Thanks guys
Bill
ps just added 2 current autotap logs to post one wot run which while @ wot 0 missfires & one misc driving and as you can see the missfires are all over the place.
Last edited by foff667; 05-08-2004 at 12:13 PM.
05-10-2004, 02:32 AM
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Try swapping them around and see if the misfire moves from the cylinder with the initial misfire to the one you swapped it to.
Also remove the coil pack wiring harness and check to make sure all the pins in the connectors are straight and free of corrosion. My bud had a high misfire count on one cylinder and when I checked out the coil pack wiring harness, found the pins in one connector to be slightly corroded. Cleaned them up the best we could and spread the pins out a little to make better contact and that cleared it up. He too was experiencing a stumble when getting on the gas.
EGR will cause a slight stumble, but not as bad as yours. Try swapping the EGR valve with a known good one anyway. Can't hurt.
Make sure all the ground wires going to the block and heads are on there good. That can cause the ECM to act weird, possibly causing your problem. This is a common problem with Turbo Regals, but any computer controlled engine will be affected. Also check for any pinched wires.
Change the fuel filter, it's cheap insurance and could be worth a little power aswell.
Your pal.
Also remove the coil pack wiring harness and check to make sure all the pins in the connectors are straight and free of corrosion. My bud had a high misfire count on one cylinder and when I checked out the coil pack wiring harness, found the pins in one connector to be slightly corroded. Cleaned them up the best we could and spread the pins out a little to make better contact and that cleared it up. He too was experiencing a stumble when getting on the gas.
EGR will cause a slight stumble, but not as bad as yours. Try swapping the EGR valve with a known good one anyway. Can't hurt.
Make sure all the ground wires going to the block and heads are on there good. That can cause the ECM to act weird, possibly causing your problem. This is a common problem with Turbo Regals, but any computer controlled engine will be affected. Also check for any pinched wires.
Change the fuel filter, it's cheap insurance and could be worth a little power aswell.
Your pal.
05-10-2004, 08:13 AM
#7
Originally Posted by SilverSurfer
Try swapping them around and see if the misfire moves from the cylinder with the initial misfire to the one you swapped it to.
Also remove the coil pack wiring harness and check to make sure all the pins in the connectors are straight and free of corrosion. My bud had a high misfire count on one cylinder and when I checked out the coil pack wiring harness, found the pins in one connector to be slightly corroded. Cleaned them up the best we could and spread the pins out a little to make better contact and that cleared it up. He too was experiencing a stumble when getting on the gas.
EGR will cause a slight stumble, but not as bad as yours. Try swapping the EGR valve with a known good one anyway. Can't hurt.
Make sure all the ground wires going to the block and heads are on there good. That can cause the ECM to act weird, possibly causing your problem. This is a common problem with Turbo Regals, but any computer controlled engine will be affected. Also check for any pinched wires.
Change the fuel filter, it's cheap insurance and could be worth a little power aswell.
Your pal.
Also remove the coil pack wiring harness and check to make sure all the pins in the connectors are straight and free of corrosion. My bud had a high misfire count on one cylinder and when I checked out the coil pack wiring harness, found the pins in one connector to be slightly corroded. Cleaned them up the best we could and spread the pins out a little to make better contact and that cleared it up. He too was experiencing a stumble when getting on the gas.
EGR will cause a slight stumble, but not as bad as yours. Try swapping the EGR valve with a known good one anyway. Can't hurt.
Make sure all the ground wires going to the block and heads are on there good. That can cause the ECM to act weird, possibly causing your problem. This is a common problem with Turbo Regals, but any computer controlled engine will be affected. Also check for any pinched wires.
Change the fuel filter, it's cheap insurance and could be worth a little power aswell.
Your pal.
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05-10-2004, 08:14 AM
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Definetly check your coil packs like SS suggested and make sure your pins to your connectors are good to go...and as simple as it sounds, are your plugs wires completlely engaged on the plug and coil pack? You know how those things can be a pain sometimes. When you tapped it, did you throw a code bacause of your stumbbling??? Also, was there any chance that you could have cracked the ceramic part of any of the plugs causing it to short? It is definetly worth a quick look...I have seen that happen before...just trying to give you some ideals.
Kepp us posted.
Kepp us posted.
05-10-2004, 08:24 AM
#9
ive got a big cam which almost automatically throws a p0300 code which julio deleted so that code will no longer show w/ autotap...after swapping the new wires I pulled all the plugs and regapped them to .040 and all the plugs were in great shape. Also with air & egr in place nothing about doing plugs & wires is really "quick" lol damn i gotta get rid of that stuff lol. I'll take a look at the coil pack connectors today and see if i cant find anything. And probably change the fuel filter again as "cheap insurance"
Thanks
Bill
Thanks
Bill
05-10-2004, 12:26 PM
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The pins that will need to get spread out a little ( just a c hair ) are the ones on the coil packs themselves. The male pins. Gently use a small screwdriver to push the pins either forward or backwards, NOT side to side because that would require more force due to the way the pins are made and could break them. This was necessary on my bud's car because on the cylinder with the misfire, the hole in the female connector in the coil pack wiring harness was a little on the loose side. This could have caused slight arcing due to a loose fit. Kinda like plugging in an old style, thin 2 prong connector from an old lamp or something into a wall socket in your house. If you wiggle it around sometimes you'll see a spark coming out of the wall socket. Same thing the engine's vibration could be doing to the coil pack harness. This slight arcing will inturn start to corrode the pins themselves.
Sorry for the long winded post, but w/o being able to show you what I'm talking about I'm trying to explain it the best I can.
And the fuel filter thing reminded me I need to change mine aswell. LOL Mine's at least 6 months old.
Sorry for the long winded post, but w/o being able to show you what I'm talking about I'm trying to explain it the best I can.
And the fuel filter thing reminded me I need to change mine aswell. LOL Mine's at least 6 months old.
05-10-2004, 02:22 PM
#12
julio from cartek tuned the car...only a dynotune though no street tune done. Most of my friends initial thoughts were that it felt like the car wasnt getting the fuel initially that it needed to run like on a carb you need that extra initial burst of fuel...the car didnt feel like it was getting it. I have an email into him so hopefully we'll figure it out soon 
05-10-2004, 02:30 PM
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Originally Posted by foff667
julio from cartek tuned the car...only a dynotune though no street tune done. Most of my friends initial thoughts were that it felt like the car wasnt getting the fuel initially that it needed to run like on a carb you need that extra initial burst of fuel...the car didnt feel like it was getting it. I have an email into him so hopefully we'll figure it out soon
05-10-2004, 04:05 PM
#14
done a ton of it and like ive stated its not a wot problem...at wot the car runs like a beast...there are no missfires but it does have some KR but then again it had the same amount before the heads/cam even when i ran 100 octane so I'll attribute it to false knock at this point. It only the off idle thing that pisses me off as it make even spinning the tires over in the water box difficult since it will stumble through it instead of spinning the tires over...then just bogs off the line no matter the launch technique. Check out my logs i posted in this thread...one is WOT & one is just driving around...if youd like to see some other parameters let me know which ones and I'll take the car out for a short spin to let ya see what it does.
lata
Bill
lata
Bill
05-10-2004, 04:15 PM
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Originally Posted by foff667
done a ton of it and like ive stated its not a wot problem...at wot the car runs like a beast...there are no missfires but it does have some KR but then again it had the same amount before the heads/cam even when i ran 100 octane so I'll attribute it to false knock at this point. It only the off idle thing that pisses me off as it make even spinning the tires over in the water box difficult since it will stumble through it instead of spinning the tires over...then just bogs off the line no matter the launch technique. Check out my logs i posted in this thread...one is WOT & one is just driving around...if youd like to see some other parameters let me know which ones and I'll take the car out for a short spin to let ya see what it does.
lata
Bill
lata
Bill
You are definetly having some missfires... 
05-10-2004, 04:22 PM
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Originally Posted by foff667
thats the thing in the back of the intake next to the oil pressure sender right? Is there anything i should look for in this instance and what normally happens when that has issues?
Maybe someone else here knows if you can verify whether or not it is bad somehow, I am sure there is away...
