what about misfire

[Jensen]

Will a bigger a stereo and a car alarm instal with a kenwood 250w amp cause my engine to misfire.....

I have got engine misfire since my instal last friday.....



Please help asap

[oneflyasianguy]

no. check your plugs, get the check engine light code with an obdII reader and do a search with it

[XYRCNCP]

:werd: I have never heard of an audio system causing engine problems...

[SQ GT-S]

Sometimes, the stereo draws WAY too much current that the battery and alternator will reach max capacity, and there is not juice left for the stereo.

Do you get a misfire when the stereo is NOT turned on? If so, then it's NOT the stereo. Check also for a vacuum hose that might have fallen off or just came loose. And also, you didn't use any wiring from the fuse block, did you? Or even from factory wires? If you tapped into the wrong factory wire(s), that could also be a problem.

Curt

[Jensen]

I had it installed at a local place. I had an alarm and my head unit installed. I went to autozone and had the codes read.

I had 6
P0171
0300
0301
0302
0303
0304

Basically all misfires, and the P0171 says "too lean on bank 1"

The guy at autozone told me that maybe the alarm is doing it, taking too much power from the engine. But, I don't get the misfire past idle, past idle, it runs ok. We erased the codes, I started my car and still the same thing, and then the check engine light came back on. I have the Kenwood DDX 7015, 6.5 LCD DVD. Maybe it is drawing too much power, if so what are my option, Lightning Cap?

Then again a vacuum hose my have been knocked off.

[Jensen]

I still get the misfire when the stereo is off....

[SQ GT-S]

Well, I have a lot of current drawing on my car and I don't have a misfire. The highly doubt the stereo is the cause of it.

Your alarm, does it tap into any wires to get an RPM signal? Perhaps on one of the coil packs of behind the gauge cluster? The only thing I can think of is that maybe they are using the wrong wire for the tach signal, and the alarm is creating a short on that wire. That would cause the RPM signal to be incorrect going into the ECU, possibly causing a mis-fire. If possible, try to disconnect that tach wire. I know it might not be easy, but that's the only thing I can think of. You can try disconnecting the power going into the alarm, but I don't think that will fix it.

Curt

[Jensen]

I am not sure what they hooked it to (alarm). I did talk to the owner, he is going to check it out again. I wish I could take care of this myself.

You may be right, that maybe casuing the misfire a idle.


I'll try and figure it out and keep you posted..