backfireing

Reply Subscribe

Thread Tools

Search this Thread

May 30, 2012 | 12:55 PM

motorhead19

Thread Starter

Newbie

Joined: Apr 2012

Posts: 20

Likes: 0

From: bonney lake

Year: 1987

Model: Cherokee

Engine: l6 4.0

backfireing

my 87 is backfireing everytime i shift above 3000rpm i did cap rotor wires and plugs but i also am running straight pipe right now. is it just from straight pipes or should i replace the coil?

thanks for the help in advance

May 30, 2012 | 03:11 PM

BuckB91XJ

CF Veteran

Joined: Nov 2008

Posts: 6,989

Likes: 4

From: Oak Harbor, WA.

Year: 1987

Model: Cherokee

Engine: 4.0 liter RENIX I-6, DIY Cold Air Intake, 2.5 FM Exhaust, 3 Core Radiator

If the cap, rotor and straight pipe is all you have done then I would have to say it's because of the straight pipe. I installed 2.5" pipe and a FM muffler on my Jeep. Sometimes when I am hammer down going through deep mud or snow and let off, my Jeep will backfire occassionally.

May 30, 2012 | 03:27 PM

BuckB91XJ

CF Veteran

Joined: Nov 2008

Posts: 6,989

Likes: 4

From: Oak Harbor, WA.

Year: 1987

Model: Cherokee

Engine: 4.0 liter RENIX I-6, DIY Cold Air Intake, 2.5 FM Exhaust, 3 Core Radiator

I also have a DIY cold air intake on my Jeep. I just think due to my mods. that my MAF sensor doesnt keep up so well when I am high up in RPMs. that is why my Jeep backfires occassionally. Other than super high RPM my Jeep runs fine...LOL, could be hitting the rev. limiter too I suppose.