Jeep Wrangler Forum banner
1 - 20 of 53 Posts

·
Registered
Joined
·
26 Posts
Discussion Starter · #1 ·
Hiya folks:

Ok, I have a running issue. Friday, on way to work, stalled in road. Would turn over, but not fire and run. Till battery died.

Victim is 2005 TJ Sport 4.0 6spd.

Replaced battery as battery was 8 years old.
Stalled again about 10 miles later. Refired and ran rest of way to work.
Stopped at FLAPS (Friendly Local Auto Parts Store), There was a CEL showing, but scanner revealed no stored code.

Resorted to google search bringing me here.

Fuel pump approx 5 years old. Can hear it prime when turn key.
Spark plugs and coil packs approx 50k miles old (OEM Iridium with 100k mile service interval).
Replaced Crank Position Sensor and Cam Position Sensor in parking lot of store.

MAF was cleaned approx 2 years ago.

1/2 tank gas from a store that stays busy, so likely good gas.

After installing Cam and Crank Position sensors, fired up with no CEL, but stalled again about 2 miles down road. Will only fire and run for ~30 seconds before stalling again, and then will not restart for ~10 min.

Fuel and air filter not very old (maybe a year.

Fuel pump relay and fuel pump fuse check out.

Ignition switch actuator pin and electrical connection replaced approx 18 months ago.

Original PCM failed (#5 injector pot popped) so junk yard computer (VIN says I should have Security system with chipped key from factory, but my TJ does not have this and has non-chipped black key), from a same 05 TJ 4.0 6spd.

As soon as it stops raining, I will take NOID detectors outside am=nd make sure injectors are receiving pulses.

How to check fuel rail pressure? Pictures of a rig to do this would be appreciated.
How to check for signal to coils?

Other things to check?

Thanks,
Hoon
 

·
Super Moderator
2006 TJ Rubicon, 4.0, automatic
Joined
·
3,202 Posts
Welcome to the forum!

When did you swap out the PCM? If it expects to see a SKIM module that could be your problem since you don’t have one.

Have you checked that all the grounds are tight, clean and don’t have any breaks/high continuity?
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #3 ·
PCM replaced 5 years ago. With non-SKIM unit. OE was non-skim (even if VIN says it should be) and replacement was non-skim.

I installed new battery harness kit from aftermarket supplier last year (all copper cables and connectors with OEM quality shielding and connectors. When I installed battery, I checked that all connections were tight (including grounds).
 

·
Registered
Joined
·
18,407 Posts
So you have history of cleaning MAF (mass air flow) even though your TJ does not even have one and replacing a fuel filter even though you TJ does not have a replaceable fuel filter?

Check actual fuel rail pressure and see what short and long term fuel trims are

Sure sounds like failing fuel pump but you playing parts darts complicates the matter as aftermarket crank and especially cam sensors are problematic at best


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
18,407 Posts
So vin build sheet says it came with a skim module but you claim build sheet is wrong?
(Vin dies not code for skim or not but vin referenced build sheet does indicate if had skim)
Was PCM replaced before most recent pcm replacement


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #6 ·
So you have history of cleaning MAF (mass air flow) even though your TJ does not even have one and replacing a fuel filter even though you TJ does not have a replaceable fuel filter?

Check actual fuel rail pressure and see what short and long term fuel trims are

Sure sounds like failing fuel pump but you playing parts darts complicates the matter as aftermarket crank and especially cam sensors are problematic at best


Sent from my iPhone using Tapatalk
Sorry for the confusion Digger. It's been a long and trying couple of days.

As for fuel filter, that is what I am calling the sock that goes over the pickup on the fuel pump when I replaced it.

As for the MAF, my mistake. I cleaned the throttle body after replacing injectors with OEM Neon injectors.

The only new parts associated with this issue are the two position sensors (I used Standard Brand as I have a long history with their parts with few to no issues), and the battery.

Everything else referenced is maintenance over last several years of ownership.
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #7 ·
So vin build sheet says it came with a skim module but you claim build sheet is wrong?
(Vin dies not code for skim or not but vin referenced build sheet does indicate if had skim)
Was PCM replaced before most recent pcm replacement


Sent from my iPhone using Tapatalk
I emailed Jeep and had line setting ticket sent to me. No reference of SKIM in that document.
When I ordered replacement PCM after injector #5 went out, was told that VIN specs that SKIM is on my jeep. Had to send PCM back because it would work on my non-SKIM TJ. (This was a two purchase ordeal with known quality vendors. (It is documented on here somewhere under an old abandoned account). Obtaining a non-SKIM PCM from a large reputable Jeep Salvage yard in the midwest got me a unit that meet to options my TJ came with and worked on my vehicle.
 

·
Registered
Joined
·
18,407 Posts
Check the rail pressure and your rail likely lacks s pressure gauge port but if you can swap to neon injectors you certainly have the ability to swap to a single level me 4.0 rail with a port from a 97-01 XJ or a 96 or newer 4.0 grand Cherokee


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
3,447 Posts
The next time she is in a non running mood see if you can hear the fuel pump prime and let us know.
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #10 ·
Swapping the rail isn't a problem. Finding one in my rural community on a weekend is.

Has anyone made a pressure testing setup that can share how they did it? Not looking to hack anything up, but more of a splice in.
 

·
Registered
Joined
·
18,407 Posts
What is the vin real easy to run it online and see build sheet instantly

Did you pull covers around key and look for module and circular antenna pickup

There is no such thing as a non skim 98-06 TJ pcm
All are skim capable just some are not skim active but three starts with skim module on the pci or ccd bus and the pcm is skim active

Perhaps you have a skim module with a key head taped near its antenna pickup

Then only a pcm programmed to your vin would work as once skim module is married to a pcm vin it stays married to that vin


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #13 ·
What is the vin real easy to run it online and see build sheet instantly

Did you pull covers around key and look for module and circular antenna pickup

There is no such thing as a non skim 98-06 TJ pcm
All are skim capable just some are not skim active but three starts with skim module on the pci or ccd bus and the pcm is skim active

Perhaps you have a skim module with a key head taped near its antenna pickup

Then only a pcm programmed to your vin would work as once skim module is married to a pcm vin it stays married to that vin


Sent from my iPhone using Tapatalk
I have been driving it for 5 years and approx 60k miles with the PCM that is installed. There is no SKIM on my Jeep, and the Jeep the PCM came out of did not have SKIM. It was reprogrammed by the local guy that does all the dealer work (contractor by name of BlueRidge Diagnostics, and he works with most all the dealerships around here, body shops, and used car lots too).
 

·
Registered
Joined
·
18,407 Posts
There is a specific tool (T hose that fits between feed line and rail with proper make and female fittings) it is listed in FSM

Once tried to make one from the big harbor freight fuel injector test kit but the fitting they had lacked the depth to push on far enough to release from fuel rail fitting

If you cobble something together be aware that a leak with 49 psi fuel plus a spark can convert a TJ to one big fire real fast


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #15 ·
What is the vin real easy to run it online and see build sheet instantly

Did you pull covers around key and look for module and circular antenna pickup

There is no such thing as a non skim 98-06 TJ pcm
All are skim capable just some are not skim active but three starts with skim module on the pci or ccd bus and the pcm is skim active

Perhaps you have a skim module with a key head taped near its antenna pickup

Then only a pcm programmed to your vin would work as once skim module is married to a pcm vin it stays married to that vin


Sent from my iPhone using Tapatalk
I have replaced the ignition actuator twice in last 100k miles (cheap a$$ peice of plastic). No SKIM module and no antennae under there.
 

·
Registered
Joined
·
18,407 Posts
I have been driving it for 5 years and approx 60k miles with the PCM that is installed. There is no SKIM on my Jeep, and the Jeep the PCM came out of did not have SKIM. It was reprogrammed by the local guy that does all the dealer work (contractor by name of BlueRidge Diagnostics, and he works with most all the dealerships around here, body shops, and used car lots too).
I repeat all 99-06 TJ pcm have skim function just some don’t currently have that function activated but it is always there waiting to see a skim module on the bus and activate


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #17 ·
There is a specific tool (T hose that fits between feed line and rail with proper make and female fittings) it is listed in FSM

Once tried to make one from the big harbor freight fuel injector test kit but the fitting they had lacked the depth to push on far enough to release from fuel rail fitting

If you cobble something together be aware that a leak with 49 psi fuel plus a spark can convert a TJ to one big fire real fast


Sent from my iPhone using Tapatalk
I will seek out the proper tool.
Thanks
 

·
Registered
Joined
·
26 Posts
Discussion Starter · #18 ·
I repeat all 99-06 TJ pcm have skim function just some don’t currently have that function activated but it is always there waiting to see a skim module on the bus and activate


Sent from my iPhone using Tapatalk
Thank you for being thorough, but I will repeat. My TJ DID NOT COME WITH SKIM. The replacement PCM that I installed on my computer DID NOT COME FROM A TK WITH SKIM. There are no SKIM components under the steering column.

The capability to run SKIM is irrelevant as it isn't needed on my TJ and the TJ it came from didn't have it either.

THE PCM IS NOT THE ISSUE (unless it has failed again). If you think it has failed, tell me how to test it. That will remove it from this conversation and I can continue to diagnose for the real issue.
 
1 - 20 of 53 Posts
Top