CEL code 16, 17, 22, 31 and now 14! -Bad Fuel Injector?

[wtdash]

Last week, after changing my intake and swapping in a JDM TD04 I got Codes 16, 17 (Fuel injector#3 and #4 inoperative), 22 (knock sensor), and 31 (Throttle position sensor abnormal voltage).

I checked the knock sensor wiring (I have the updated/uncracked knock sensor), cleaned it up a bit, cleared the codes and seemed to fix it.

This week I swapped in the TD05 and @ the Autocross today I got code 14 - nothing else. Car wouldn't idle well, and during the break I tried to clear the code, but it wouldn't go away.

I've been running w/480cc injectors but running the Revtronix chip set for 440's (long story, ...) so I swapped in an extra chip I had for the 480's, but it didn't make any difference......

......, so I dropped out of the race and headed home.

On the way home the car DID clear up after about 20 mins...a mix of highway and freeway driving - 45-70MPH, and ran fine the rest of the way home and CEL.

Any feedback is appreciated!

UPDATE:

[gijonas]

So what exactly is your problem at this point.Obviously it has to do with your latest changes,retrace your steps.

Did you use your old harness or new?

Different injectors then before?

Same or different TPS?

After clearing - what codes now?

[log1call]

Since it cleared itself on the way home I'd say it isn't a mechanical/electrical problem but rather a tune problem.

These cars learn your driving patterns and the state of wear in the engine and they attempt to adjust things to suit. Turnng up at race day and expecting the car to suddenly learn a new style/conditions, when it is already struggling to keep all the parameters within acceptable ranges with your modificatins, may well be too much for it.

You could retune or you could spend a few hours teaching the car track conditions and driving style before going out there and going hard.

[wtdash]

You could retune or you could spend a few hours teaching the car track conditions and driving style before going out there and going hard.

I don't disagree, as I haven't got any serious miles/hours on the new intake and turbo(s) to work out the bugs, plus it was almost 100 out there today (although temp gauge never moved above normal).

However, I've AutoX'd twice before w/out issue.

[wtdash]

So what exactly is your problem at this point.Obviously it has to do with your latest changes,retrace your steps.

Problem is the codes and not knowing what's causing them, I went thru it after they appeared the 1st time...obviously need to do it again.

Did you use your old harness or new?

The harnesses never changed during the turbo swaps.

Different injectors then before?

Same - 480cc

Same or different TPS?

Same TPS.

After clearing - what codes now?

I never manually cleared the codes - the car just started to run better after time on the highway.

I just went out and checked.... the code is still there, the car runs poorly and I was unable to clear the codes...so don't understand why it would 'clear up' while driving????????

Thanks,
Td

[ericem]

less heat is my guess thats for sure.

[Legacy777]

Have you checked your grounds and wiring from the injectors to the battery?

[wtdash]

Not yet...was thinking of doing a 'grounding mod' to eliminate any grounding issues.

[Legacy777]

Might not be a bad idea. Also, check the connectors behind the battery and make sure there's no corrosion in them.

[91legacyawdturbo]

Might not be a bad idea. Also, check the connectors behind the battery and make sure there's no corrosion in them.

Do it to all of your connectors and add some dielectric grease to them.

[wtdash]

UPDATE:

Did as suggested above - checked connectors and added dielectric grease, and followed most of ScottyS' grounding suggestions.

With the key OFF, I checked the Resistance on all the injectors and cyl. 2-4 were ZERO; Cyl. 1 was 2+Ohms...Same one I was getting the Code 14 (Fuel injector #1 inoperative) on.

Infinity resistance @ the injector plugs.

Turn the key ON; engine OFF and 9+ volts on all the plugs.

Time for new injectors?

I'm not 100% sold on bad injectors as I had Code 16 and 17 a couple weeks ago, but didn't check/test the injectors, so not sure why they'd be OK now???? Could still be the wiring?

BTW, these are JDM 480cc I bought used, had flow tested and put about 5K miles on them.


Thanks

[Legacy777]

Todd,

Injectors shouldn't have 0 resistance. The stock injectors should be about 11-12 ohms across the two terminals of the injectors.

Is this how you tested those injectors?

[wtdash]

Crap...used wrong setting -20k vs. 200....

Tested again and two of the injectors were 11-12 ohms, one was 15, and the 'bad' one was infinite.

I went ahead and swapped in the 440's I have, reset the ECU (disconnected battery overnight) and so far, so good. Still letting ECU learn , so no hard pulls yet.

Thanks

[Legacy777]

Yes, if you had one injector that was infinite....it's bad.