misses when under hard bost

Nocheez

Probably posts too much
Apr 17, 2005
271
0
0
Charlotte, NC
Try autolite copper plugs. I had a high end misfire which appears now to have been spark plug blowout. It was the best $7 I ever spent, and they are so cheap and easy to replace that I won't mind doing it every 10K miles if I have to.
 

supraguy@aol

Well-Known Member
Dec 30, 2005
4,232
37
48
Atlanta
I didn't see you mention in the thread, but how old are the wires?
Maybe check the resistance on them, and more importantly, check to make sure the boots that go onto the plugs are completely DRY. Any oil/water/coolant that gets on them can make the wires ground to the cylinder head instead of sending the spark into the plug. This happened to me, and ONLY happened under boost/ engine load.
 

Grimsta

Supramania Contributor
May 30, 2007
1,081
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Santa Rosa, Ca.
SO this isnt solved yet? Do you have an aftermarket intake on your car?

Seems like a completely unrelated dumb question, but just answer it and i'll tell you why
 

thebuddrik

New Member
Jun 2, 2007
149
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45
Lafayette ,La.
my ground wire is a little frayed where it is connected to the coil pack.

my plugs are brand new denso from toyota

my wires are about a year old, they have a slight layer of oil at the base of them.

yes, i have an after market air filter.

thanks guys
 

thebuddrik

New Member
Jun 2, 2007
149
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Lafayette ,La.
Grimsta;1020001 said:
Right there, what kind of MAF adapter you got on there? Take a pic and show me.

It a cheap filter and bracket that came with the car. I am gona change it soon. The problem is I blew my whole wad on everything else. I can get you the pic. but can you tell me why this would cause my problem. Before the burnt valve , and the head work the car ran fine.
Thanks
 
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Grimsta

Supramania Contributor
May 30, 2007
1,081
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Santa Rosa, Ca.
Ew, you blew your wad on your car? I hope you cleaned that up! ;)

The MAF adapter, if it doesnt sit square on the honey comb will throw off air readings and cause your jerking under boost. Also if the intake air has a bend right before the MAF it will do the same thing. The mafs need to have the honey combs wide open and the air has to hit it dead on. It was a pain in the ass fixing this issue when we were making the bolt on CAI, had to get just the right MAF adapter
 

CarlosPTR210

New Member
Apr 5, 2006
435
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Calexico,CA
www.ptr.com.mx
Grimsta;1020419 said:
Ew, you blew your wad on your car? I hope you cleaned that up! ;)

The MAF adapter, if it doesnt sit square on the honey comb will throw off air readings and cause your jerking under boost. Also if the intake air has a bend right before the MAF it will do the same thing. The mafs need to have the honey combs wide open and the air has to hit it dead on. It was a pain in the ass fixing this issue when we were making the bolt on CAI, had to get just the right MAF adapter


:aigo: I need to modify my :cry:
 

thebuddrik

New Member
Jun 2, 2007
149
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Lafayette ,La.
let me put that a different way, "SPENT ALL OF MY MONEY". $1600 on all of my stuff and damn near $400 on a ebay head that wasnt worth a crap and the guy wont give me my money back. is that better?
 

thebuddrik

New Member
Jun 2, 2007
149
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0
45
Lafayette ,La.
Took the car for lunch and found out that if I down shift it starts to miss, but it continues to accelerate while missing. If i dont down shift and just give it the gas it will bost up and not miss until high rpms.
 

thebuddrik

New Member
Jun 2, 2007
149
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Lafayette ,La.
p1020679_1.jpg

here you go, tell me why you think this could my problem
 

Grimsta

Supramania Contributor
May 30, 2007
1,081
0
0
Santa Rosa, Ca.
Take the filter off and take a pic of the honeycomb on the inside for me. It does look alright but it could be covering up part of the honeycomb
 

thebuddrik

New Member
Jun 2, 2007
149
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Lafayette ,La.
i dont think it is. when i had everything disassembiled i took a lot of time inspecting everything and cleaning things that could be cleaned ( no i didnt try to clean the AFM sensor, I did spray the honeycomb with electra clean with the sensor removed ). I would have noticed if abything was covering up the honeycomb.
i still cant help but thinking that it has to be something that I did because it wasnt doing it before.
 
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A-to-the-J

Panda™ and Pre-89 Gracer™
Feb 19, 2006
1,080
1
38
38
Anaheim/West Covina, CA
thebuddrik;1020702 said:
i dont think it is. when i had everything disassembiled i took a lot of time inspecting everything and cleaning things that could be cleaned ( no i didnt try to clean the AFM sensor, I did spray the honeycomb with electra clean with the sensor removed ). I would have noticed if abything was covering up the honeycomb.
i still cant help but thinking that it has to be something that I did because it wasnt doing it before.
he's talking about when the AFM Adapter is mounted to the AFM, if it's covering up part of the honeycomb (most likely the corners of it)
 

thebuddrik

New Member
Jun 2, 2007
149
0
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45
Lafayette ,La.
sorry guys but i will say it again, the car ran fine a month ago. i tore it apart, had the head rebuilt, changed a bunch of hoses, new plugs, new injector clips.
thanks for all of the help
 

thebuddrik

New Member
Jun 2, 2007
149
0
0
45
Lafayette ,La.
this is a major pain in the ass. i have to go on a 2 1/2 hr road trip in about 1 hour and i dont want to take the car because i am scared if it is the ignition and it went out on me i would be screwed.
honestly i dont think it is an ignition prob because if i am on the hwy and i dont down shift and just give it the gas it boosts up and accelerates. it only misses when i down shift and get on it. the prob isnt solved yet.
thanks