Novak Conversions Jeep Wrangler TJ engine mounts

P0204 open circuit

Cprems

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Oct 31, 2024
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In the JEEP South
Good evening guys and girls,

Jeep ran flawlessly 20 miles out to our daughter's softball game and on the way home started running rough and temp was fluctuating (running lean maybe?) with noted loss of power and CEL. The CEL was blinking on the Interstate. We nursed it home, let it cool down and ran better. Took it out for another test drive and it went back to running rough and CEL back on. Here is what I have done so far:

P0204 (open circuit injector 4) code.
Checked both battery and alternator for the correct power and charge. 13.6-14V
Ran a continuity test on injector 4 wiring from PCM to the injector (good)
Hooked up my test light and checked pulses on all 6 injectors (good) Similar to a Noid test but less accurate.
Stethoscope to injectors and can hear the clicking pulses on each injector.
Ohmed out all six injectors, looking for 12 Ohms +/- 1.2 Ohms @68* (weather currently 71 outside.) Looking for 10.8-13.2 Ohms as a low and high.

Injectors -
1. 13.3
2. 13
3. 13.3
4. 13.5 (open circuit code on this injector) Also saw a split on the backside of this one as well.
5. 13.3
6. 13.2

Only two of my injectors seem to be within the high tolerance range (13.2) It appears that it very well may be time to change out injectors. Is there anything else I can check and verify they're going bad?

Where are y'all purchasing said injectors from?

Any input greatly appreciated, any testing I need to do, let me know.

Thanks as always.
 
I bought a set of injectors from Precision Auto Injector for my 97. Siemens OEM rebuilt and paid for a balanced set. Discount code Jeep gets you 10 per percent off.

I also installed DEI's fuel rail insulation.

IMG20230313105430.jpg
IMG20230313160812.jpg


-Mac
 
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Reactions: Cprems
I just purchased some reman Denso injectors from a guy on Ebay. Had great reviews and in business since 2009. $100. I also replaced all my injector harnesses this afternoon. Making progress.
 
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Reactions: tr21triton
Quick update - installed a new valve cover gasket, DEI heat soak kit, new injectors and soldered on new injector wires. So far, it's running like a champ and I'm quite impressed with the new injectors. I'll keep y'all updated on them.
 
Novak Conversions Jeep Wrangler TJ engine mounts