Hello everyone. My fiancee just bought a '99 5.2. She drove it for apx 300 miles without any problems. One evening on her way home the dreaded check engine light came on...I had it scanned and showed open circuit fuel injector #5. I have replaced the injector and installed all new plugs and wires. The same code is present after having it reset. It idles rough and a noticeable loss in power. I have searched and read many possibilities. I would like to try and troubleshoot for a possible short. Any ideas where the most common short is found? Any other ideas are greatly appreciated as she lives in a small town and I am driving about 90 miles to check on it. Thanks!

 

Ok...here is a list of the things I have tried and tested so far.
Tested all injectors with a noid light (all pulsed)
checked the voltage and resistance on all the injectors (13.8v and 13 - 13.4 ohms)
checked voltage on TPS 5.1v continuous and .59 - 3.6v on the throttle (can someone tell me if 3.6v is correct because specs show 4.5v)
checked for spark at all the plugs

I am hearing a ticking (almost a knock) at idle. As throttle is increased it goes away.

Any ideas?

Thanks!

 

TPS needs replaced and tuned. Max should be 4.5 volts out and thats WOT (wide open throttle). Also concitering you have 5.1 volts going in I think your multi-meter could be off + .1 but unsure as .1 is very little.


What spark plugs did you use and did you route the wires off the motor. (There is a TSB on that). What exact spark plugs and wires did you use?

 

Thanks for the response. Yeah I just bought an old cheapie meter from Harbor Freight so it could be off a little, I was thinking it was prob the TPS since the voltage stopped at 3.6 at WOT. I just found the TSB on the re-routing this morning at around 4...lol. So those are my next steps. Not sure the exact part numbers for the plugs and wires but the plugs were Autolite non platinum gapped at .40 and the wires were Mopar...I will look to see when I head back down there this evening (90miles away...lol). How do you go about tuning the TPS?

 

The plugs are Autolite copper core 5224 and the plug wires are actually Omnispark 9404.

Here's whats new. I re-routed the plug wires per the TSB and installed a new TPS (after the new install I checked the voltage again. It showed .75v at idle and smooth up to WOT and it only showed 3.75v). I cleared the code. The CEL with p0205 came back within a quarter mile. It still has a miss and runs rough. There is a tapping/knocking that I cannot pinpoint (sounds like the lower half). Kinda running out of ideas.

Could this all be caused from timing chain stretch or a bad timing chain tensioner?

 

You have the wrong plugs in there. Pull them out and get Champion (Cheapo $2 dollar) Regular Cooper plugs. That is your first HUGE mistake!

 

Ok...I have replaced the Autolite with the Champion copper 436. Still the same symptoms.

 

i have never heard of thos "omnispark" plugs, maybe get a good set of msd or mopar performance wires

 

Thanks for the responses...but the problem was there before I changed anything out. Its probably time to just put it on the computer.

 

Well the wires are not good as Sharp is saying. These trucks are VERY picky!

One thing I see that you didn't do was change out the distributor cap and rotor. Go to Auto Zone or whatever and get a cap and rotor with brass contacts. Do It Yourself (top questions and answers) FAQ's


The only 2 other things it could be is a Crankshaft Sensor or Pickup Sensor which I would lean more towards a pickup. If you do the PCM you can go to Ebay and get a pre-flashed one for about $120 for a drop in ready to go unit. You will need the VIN#, Mileage, and Motor.