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-   Technical Discussion and Customizing your H2 (http://www.elcovaforums.com/forums/forumdisplay.php?f=5)
-   -   Random/Multiple Cylinder Misfire Detected (http://www.elcovaforums.com/forums/showthread.php?t=28877)

datapimp69 08-05-2007 09:23 PM

Random/Multiple Cylinder Misfire Detected
 
well my H2 has just started throwing this code.

when i am at WOT, it does surge or hesatate, the tach does go up and down.

i do have a super charger on it and a borla exhaust.

anyone else have this problem.

oh... i have been trying diffrent brands of gas since this started to see if i was getting some bad gas.

HUMTECH 08-05-2007 09:39 PM

Re: Random/Multiple Cylinder Misfire Detected
 
Likely have A restricted cat converter. Check backpressure of both if either is over 1 psi of backpressure that will cause random missfires on that bank.

H2 Bill 08-06-2007 05:10 PM

Re: Random/Multiple Cylinder Misfire Detected
 
HUMTECH is right (as usual!). I had the same thing happen last week. I got the same code and have been getting a code for a bad passenger side converter too. It happened when going up a steep incline and punching it hard and the check engine light kept blinking on and off. I downloaded (if I remember correctly) code P101. I have a supercharger also.

datapimp69 08-08-2007 06:09 PM

Re: Random/Multiple Cylinder Misfire Detected
 
i forgot to mention that i had high flow cats installed. there is allmost nothing in there and cant see how it would make any back pressure but i will check it

H2 Bill 08-08-2007 09:50 PM

Re: Random/Multiple Cylinder Misfire Detected
 
Where in the world did you find hi-flow cats for the H2?

datapimp69 08-09-2007 12:53 AM

Re: Random/Multiple Cylinder Misfire Detected
 
Quote:

Originally Posted by H2 Bill
Where in the world did you find hi-flow cats for the H2?


just find the right size and put them on.

here is what i bought

http://store.summitracing.com/partdetail.asp?autofilter=1&part=DTC%2D79%2D400250 &N=700+0&autoview=sku

IRA51 08-09-2007 01:15 AM

Re: Random/Multiple Cylinder Misfire Detected
 
what code # is it throwing ? on a side note you could have gotten the Random tecnoligy cat to fit in the H2 without any problem ,and I hear they claim to be the freest flowing.

HUMTECH 08-11-2007 11:28 PM

Re: Random/Multiple Cylinder Misfire Detected
 
Ummm well the stock converters when working properly have less than 1psi backpressure, hard to get much flow increase over that.

H2 Bill 08-13-2007 06:47 PM

Re: Random/Multiple Cylinder Misfire Detected
 
Quote:

Originally Posted by IRA51
what code # is it throwing ? on a side note you could have gotten the Random tecnoligy cat to fit in the H2 without any problem ,and I hear they claim to be the freest flowing.


At first I got the po420, I replaced the driver side cat and then got the po430 and replaced the passenger side. No codes since.

IRA51 08-13-2007 11:40 PM

Re: Random/Multiple Cylinder Misfire Detected
 
have you checked to see if the headers havent burned the plug wires? old cheap skates way to check plug wires . get a spray bottle and spay the plug wires a night and start the truck if you see sparks the wires are shot . a DVOM will also work no water needed.


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