#1 cylinder is not firing, what are the possibilities?

**DYZ** · 10-04-2013, 03:58 PM

Hello All,

While driving on the highway today, the check engine light suddenly started to flash and later stayed on. Engine also started to run really rough with lost of power. After I got home I did some diagnosis work and determined that #1 cylinder is not firing. I have a backup coil pack, but it doesn't help after I put it on. I also swapped the #1 and #2 injectors, yet #1 cylinder is still not firing.

Is there a way to check if an injector is getting power on these cars? I used a 12v test light on the injector plugs, but the light showed no pulsing on any of the injectors. So I'm not sure this is the right way to test it.

Any idea what else could go wrong? At this moment I'm kind of lost, any suggestions are welcome.

Thanks!

**DYZ** · 10-04-2013, 05:08 PM

BTW, I also swapped the spark plugs which didn't make a difference (#1 is still not firing after the swap). The wires seem to be in good shape too ... I'm really puzzled.

**howardc64** · 10-05-2013, 09:17 AM

You can try a cheap inline ignition tester to determine if the spark plug fires. This helps to decide whether to chase no spark or no fuel condition.

http://www.autozone.com/autozone/acc...er=900800_0_0_

**DYZ** · 10-05-2013, 10:48 AM

Thanks, Howard. I actually just did some more tests and it doesn't look good.

I tested with an ignition tester and it does fire. I tested the injector again and it also pulses (previously I thought the pulse comes from the positive wire when in fact the ground wire provides the pulse). The last test is the compression test. I bought a $20 test kit from HF (#69885) this morning. It worked pretty good, but the result is not what I want to see... #1 cylinder only has 30 psi when dry while the rest cylinders constantly read 165 psi. Wet test on #1 reads about 40 psi, so it looks like I have a bad exhaust valve.

I don't remember seeing anyone reporting a similar issue on this board ... So it sucks to be a first

The car now has 155K miles and I'm not sure what I'm going to do with it. Anyone know what the job would cost for such repair in NE area?

**DYZ** · 10-09-2013, 07:30 AM

Dealer wants $3.5K ~ $4K for the job. That's about what car is worth for trade-in when it's in fair shape. At this moment I'm leaning toward pulling the head myself and send it out for rebuild. This will be a first for me. If anyone has done this before on these cars, please mention what are the things that I need to watch for when tearing it apart. Thanks!