Thealien

iTrader: (2)

I installed a very low mileage 2005 5.3 into my 1972 GMC Jimmy. I have been getting a lean bank 1 code since I started it. Thinking it was an intake leak we used a smoke machine and found no leaks. Thought it might be a bad O2 so I replaced it. I brought it to a local tuner and he says cylinders 1 & 3 are not firing (manifold stays cold on those cylinders). He said compression is around 200 on both cylinders. There is an injector pulse and spark.

Could an injector be bad and not throw a code? Any suggestions? I spent 4 months doing this swap myself. Have a couple of good mechanics who have been unable to fix the problem. I am really getting frustrated, please help!

Mark

Darkman

iTrader: (2)

If you pull the plugs for #1 and #3 after running, are they wet or dry?

Have you tried swapping the #1 and #3 injectors with some of the others?

Thealien

iTrader: (2)

Not yet. Just trying to get some ideas.

JUICED1

iTrader: (3)

Make sure the injectore are pluged in all the way. Could be a loose conection.

mark_H14

i would say that it is also a loose connection..

Thealien

iTrader: (2)

Wouldn't a loose connection throw a code?

We are getting an injector pulse signal. We are getting spark.

Thanks

JUICED1

iTrader: (3)

Unplug it and check, that way you know for sure. I can't say I"ve ever left any unplugged before.

OMGWTFBODY

iTrader: (5)

With an injector unplugged, the motor will run like ****. It will not throw a code until it reaches closed loop. With 2 misfiring, it will take a while.

After closed loop is reached, it will flash SES and go into limp mode.

I don't wanna know how I know this.

Thealien

iTrader: (2)

That is the strange thing, no misfire codes. The engine has been run quite a bit (50 miles) and is not in limp mode?

The only code I have gotten is lean bank 1?

Thealien

iTrader: (2)

Well I bought some used injectors with only about 100 miles on them. The number 1 injector was very clogged. I replaced 1 & 3 and it is running much better now. I am thinking of sending them off for cleaning and flow matching. Any suggestions on where to send them?

Thealien

iTrader: (2)

Here is the injectors for cylinders 1 & 3

JUICED1

iTrader: (3)

Good catch on the dirty injector. How many miles did your old ones have where they got that clogged. No clue where to get them cleaned. Sorry.