Engine sputters During WOT C5 Corvette *Help*
Thread Starter
Joined: May 2005
Posts: 1,410
Likes: 11
From: Port St. Lucie, Fl
Engine sputters During WOT C5 Corvette *Help* Any ideas what it could be? Its a 2002 automatic highly modified with supercharger.
On take off at Wide open throttle after 3500 rpms its sputters or shakes a bit. Am I running only on 7 cylinders? Would this typically happen. I did get a P0200 code a week ago but had a faulty fuel injector. Need thoughts Thanks
Someone from another forum said, I should check my spark plugs, but I already changed them out about a month ago, Should I recheck them? Stumped?
On take off at Wide open throttle after 3500 rpms its sputters or shakes a bit. Am I running only on 7 cylinders? Would this typically happen. I did get a P0200 code a week ago but had a faulty fuel injector. Need thoughts Thanks
Someone from another forum said, I should check my spark plugs, but I already changed them out about a month ago, Should I recheck them? Stumped?
Last edited by corvet786c; Jun 25, 2015 at 06:21 AM.
Thread Starter
Joined: May 2005
Posts: 1,410
Likes: 11
From: Port St. Lucie, Fl
I can say though when I gapped the TR6 plugs to .35 wondering if they are blowing out? Causing the sputtering under WOT. I am running a 4.38 pully about 7lbs of boost, Should I make the gap tighter to about .30 ?
When the car was tuned the tuner had the mechanic gap the plugs to .25, but I opened them up a bit. Should I put them back to .25 then? Are my plugs blowing out under boost? Its not that much boost though?
Maybe the coils are weak and the gaps should be tighter? Thoughts?
On The Tree
Joined: Jun 2015
Posts: 182
Likes: 3
From: Portland OR
When did you open up the plug gap? During recent plug change?
Since you did a recent plug change I would be looking in that area.
Close the gap down to .025 and see what happens.
Or open the gap more and see if it gets worse! :^)
You didnt use some kaka exotic plugs did you?
With the boost you should use a non-extended tip plug in a normal heat range and I suggest standard copper core cheap plugs.
Remember there are more than just the connectors at the injectors....
Since you did a recent plug change I would be looking in that area.
Close the gap down to .025 and see what happens.
Or open the gap more and see if it gets worse! :^)
You didnt use some kaka exotic plugs did you?
With the boost you should use a non-extended tip plug in a normal heat range and I suggest standard copper core cheap plugs.
Remember there are more than just the connectors at the injectors....
Thread Starter
Joined: May 2005
Posts: 1,410
Likes: 11
From: Port St. Lucie, Fl
When did you open up the plug gap? During recent plug change?
Since you did a recent plug change I would be looking in that area.
Close the gap down to .025 and see what happens.
Or open the gap more and see if it gets worse! :^)
You didnt use some kaka exotic plugs did you?
With the boost you should use a non-extended tip plug in a normal heat range and I suggest standard copper core cheap plugs.
Remember there are more than just the connectors at the injectors....
Since you did a recent plug change I would be looking in that area.
Close the gap down to .025 and see what happens.
Or open the gap more and see if it gets worse! :^)
You didnt use some kaka exotic plugs did you?
With the boost you should use a non-extended tip plug in a normal heat range and I suggest standard copper core cheap plugs.
Remember there are more than just the connectors at the injectors....
So I researched NGK TR6 (thats whats on their now) and alot of boosted cars are running .35 gapped. So this weekend going to change it back to .25.
The only code I got was a P0200 code for faulty injector, which I changed out. My idle now just seems a lil off.
When I first gapped to .35 I thought the car ran great for a couple of days felt stronger and the idle was more consistant not up and down.
So unless there is another issue don't know where else to look.
I did ohm the coils and very interesting info here. I bought a new coil from auto zone (denso) and it ohmed around 50-55. Then I ohmed some of my older coils and they ohmed around 100-105. Are they loosing resistance and spark? Would newer and good stock coils ohm lower than faulty ones?
Thread Starter
Joined: May 2005
Posts: 1,410
Likes: 11
From: Port St. Lucie, Fl
*All fixed* Combination of the blower and fuel was blowing out the spark. Re gapped to .25-.22, much better idle and does not sputter as much, but maybe coils are going bad. It is much better.
On The Tree
Joined: Jun 2015
Posts: 182
Likes: 3
From: Portland OR
NGK TR6 plugs are extended tip plugs.
This style pug is not recommended for boosted applications.
The ground electrode is too long and will not cool properly.
Do a couple of hard long rips and pull the plugs and look at the ground electrode, I'll bet it has turned blue from heat.
Go back to a standard heat range plug for a boosted application (those are 1 range cold) and a non-projected tip plug. The plug heat range is for the center electrode.
A non-projected tip will have a shorter ground electrode, thus better cooling for the ground electrode. Will probably help with WOT miss-fires.
The boosted CTS motor calls for a TR6GP but that is an extended tip plug as well.
I would try a BR5EF But I think they were discontinued.
You want a plug like this http://www.summitracing.com/parts/ngk-3346/overview/
But not a 7 heat range you want a 5 or 6
This style pug is not recommended for boosted applications.
The ground electrode is too long and will not cool properly.
Do a couple of hard long rips and pull the plugs and look at the ground electrode, I'll bet it has turned blue from heat.
Go back to a standard heat range plug for a boosted application (those are 1 range cold) and a non-projected tip plug. The plug heat range is for the center electrode.
A non-projected tip will have a shorter ground electrode, thus better cooling for the ground electrode. Will probably help with WOT miss-fires.
The boosted CTS motor calls for a TR6GP but that is an extended tip plug as well.
I would try a BR5EF But I think they were discontinued.
You want a plug like this http://www.summitracing.com/parts/ngk-3346/overview/
But not a 7 heat range you want a 5 or 6
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Thread Starter
Joined: May 2005
Posts: 1,410
Likes: 11
From: Port St. Lucie, Fl
The P0200 code is related to (electrical) either an injector or injector harness, on my corvette, I checked the wiring harness made sure no cracks, cuts, etc etc no shortage. The motors move back and forth under hard acceleration and can cut wires in the rear behind intake manifold. Also heat from headers can damage those lil wires. Well my wires were ok. I also checked the ends of injector harness connections and make sure there was pulses going thru. Everything worked out ok.
Also I was gettin a popping that was driving me crazy, during idle. Long story short. To check injectors make sure they are opening and closing correctly and not clogged.
Take the red and black + and - wires from an ohm meter and place the ends on a 9volt battery + and - and the probes on the connecting metal part of the injector.
Check all injectors by listening to then open and close properly they all should be making the same sound, (clicking) if you hear 1 injector that makes a diffrent clicking sound then the others, that is the faulty injector setting off the P0200 code because it is not properly opening and closing and the pcm is reading its pulses.
Hope this helps.
Last edited by corvet786c; Jun 30, 2015 at 07:37 AM.
This is going to save you a lot of time, so read carefully,
The P0200 code is related to (electrical) either an injector or injector harness, on my corvette, I checked the wiring harness made sure no cracks, cuts, etc etc no shortage. The motors move back and forth under hard acceleration and can cut wires in the rear behind intake manifold. Also heat from headers can damage those lil wires. Well my wires were ok. I also checked the ends of injector harness connections and make sure there was pulses going thru. Everything worked out ok.
Also I was gettin a popping that was driving me crazy, during idle. Long story short. To check injectors make sure they are opening and closing correctly and not clogged.
Take the red and black + and - wires from an ohm meter and place the ends on a 9volt battery + and - and the probes on the connecting metal part of the injector.
Check all injectors by listening to then open and close properly they all should be making the same sound, (clicking) if you hear 1 injector that makes a diffrent clicking sound then the others, that is the faulty injector setting off the P0200 code because it is not properly opening and closing and the pcm is reading its pulses.
Hope this helps.
The P0200 code is related to (electrical) either an injector or injector harness, on my corvette, I checked the wiring harness made sure no cracks, cuts, etc etc no shortage. The motors move back and forth under hard acceleration and can cut wires in the rear behind intake manifold. Also heat from headers can damage those lil wires. Well my wires were ok. I also checked the ends of injector harness connections and make sure there was pulses going thru. Everything worked out ok.
Also I was gettin a popping that was driving me crazy, during idle. Long story short. To check injectors make sure they are opening and closing correctly and not clogged.
Take the red and black + and - wires from an ohm meter and place the ends on a 9volt battery + and - and the probes on the connecting metal part of the injector.
Check all injectors by listening to then open and close properly they all should be making the same sound, (clicking) if you hear 1 injector that makes a diffrent clicking sound then the others, that is the faulty injector setting off the P0200 code because it is not properly opening and closing and the pcm is reading its pulses.
Hope this helps.
That does help. I'll check that tonight to see if I can track down which one is giving me a headache. I think it's on the passenger side as I'm seeing the fuel trims higher there, which leads me to believe that I possibly have a clogged injector or troubled injector on that side.
Thread Starter
Joined: May 2005
Posts: 1,410
Likes: 11
From: Port St. Lucie, Fl
Because injectors ohm resistance all the same even if they are faulty. But the sound of clicking can tell if properly opening or closing.
Yep same thing has happened to me on passenger side too, sometimes ran good other bad. Probably a faulty injector. Go through each one individually and listen to the clicking of opening and closing if 1 sound diffrent that is the faulty one. This is the only test that works.
Because injectors ohm resistance all the same even if they are faulty. But the sound of clicking can tell if properly opening or closing.
Because injectors ohm resistance all the same even if they are faulty. But the sound of clicking can tell if properly opening or closing.
I've been using the EV1 to EV6 adapters that I bought off ebay, and I have a feeling that they are not working well and could be causing my issue. I have new EV6 pigtails that I need to solder into my factory harness to eliminate that as the root cause. Hopefully that's it.
Thread Starter
Joined: May 2005
Posts: 1,410
Likes: 11
From: Port St. Lucie, Fl
Well I checked all the injectors last night with a 9v battery, and they all sounded the same, so I don't think it's an injector issue.
I've been using the EV1 to EV6 adapters that I bought off ebay, and I have a feeling that they are not working well and could be causing my issue. I have new EV6 pigtails that I need to solder into my factory harness to eliminate that as the root cause. Hopefully that's it.
I've been using the EV1 to EV6 adapters that I bought off ebay, and I have a feeling that they are not working well and could be causing my issue. I have new EV6 pigtails that I need to solder into my factory harness to eliminate that as the root cause. Hopefully that's it.