Originally Posted by alexh2

terminator,

I just got my injectors back in - pretty big job on this truck.

As I said above I located a bad injector. The resistance was twice the spec. truck runs/idles better than it has in years.

I did run it a few times at full throttle up to red line and I felt no loss of power through the whole power band. I have to think it was the injector because the power loss was very noticeable before.

The theory would be that a weak injector would show up as a slightly to very rough idle. However, at power the cpu could compensate for the weak injector by turning up the output of the other units. It would do this based on feedback from the o2 sensor and of course it has no way of knowing that there is a weak injector unless it gets so bad that it detects a total miss. However, at full load, the injectors would max out and result in a loss of power, like fuel cut was hit.

You can easily check the passenger side injector resistance by pulling the connectors and measuring the resistance. It should be about 14 ohms at room temp. Just be extremely care not to break the connectors. The drivers side are not accessible.


If you don't find a problem there you might be able to check the resistance of the drivers side injectors by pulling the connector on the ECU but it won't be fun.

The other way to diagnose this might be to check emissions if you have access to a friendly shop. I had to smog my truck about 6 months ago and it barely passed NO which can indicate a lean condition.

My truck was like this for several years. Hopefully I didn't burn the valves too bad on that cylinder.


Good luck