2005 4.0 wont start

[Animatedmean]

Hey Everyone, Have a new to me 05 4.0 TJ picked it up non running. It will crank all day and never start. I tested coil has spark on all 6 on the rail. installed new plugs, Tried some starting fluid no luck. I smell gas when tring to start it. compression test all 155-170 range. No check engine light not sure where to go next any ideas ?

 

[hear]

Welcome to the forum. These are the best kind of jeeps to pick up. Hopefully you pretty much stole it from the guy because he couldn't get it started and just needed it out of his driveway. You'll probably have it running in less than a week and less than $100 invested.

I think I'd check the ASD relay next, and then verify fuel pressure just to completely rule that out. Were the plugs you took out fouled? After that I think I'd be thinking cam or crank position sensors. If you have fuel, air, and spark, then either you don't have enough fuel, enough spark, or spark at the correct time.

 

[Animatedmean]

Welcome to the forum. These are the best kind of jeeps to pick up. Hopefully you pretty much stole it from the guy because he couldn't get it started and just needed it out of his driveway. You'll probably have it running in less than a week and less than $100 invested.

I think I'd check the ASD relay next, and then verify fuel pressure just to completely rule that out. Were the plugs you took out fouled? After that I think I'd be thinking cam or crank position sensors. If you have fuel, air, and spark, then either you don't have enough fuel, enough spark, or spark at the correct time.

I picked it up for $1200 so i couldn't pass it up. I have a 97 tj also so done my share of wrenching on them but no CEL has me stumped. I will google the ASD relay is there a way to bypass it ? Plugs looked rough 2 had cracked insulators the ceramic part so i replaced them all they had been in there a long time it looked like. UPDATE swapped ASD relays with another relay no change i ordered a OEM crank sensor it will be here Friday

 

[Uncle Salty]

Sounds like you’re diagnostic method is sound so far. Hear is spot on with his suggestion. I’d check for codes with the key on/off method as well. With an ’05, you can’t rule out a toasted PCM.

 

[Animatedmean]

Sounds like you’re diagnostic method is sound so far. Hear is spot on with his suggestion. I’d check for codes with the key on/off method as well. With an ’05, you can’t rule out a toasted PCM.

Any way to test PCM ? or any tips on a swap ?

 

[hear]

Wranglerfix is the absolute go-to, he prefers to be paid via personal check or a ups box full of pennies. There are some known PCM issues with the later models.

 

[Uncle Salty]

Don’t fixate on the PCM just yet. I always verify the wiring first then the sensor/component. So verify the ASD and CKP/CMP sensor circuits as hear suggested.

 

[CAD1]

I believe several people have recommended Flagship One if you need to replace the PCM

 

[CAD1]

I did have this happen to me. I changed the CPS, no luck. Then changed the entire distributor, including Ckp, plugs, wires and coil - worked. No issues since

 

[JKP]

Turn the key On, Off, On, Off, On without starting it. Any codes will display in the odometer. This will also verify the PCM is alive.

 

[Animatedmean]

Turn the key On, Off, On, Off, On without starting it. Any codes will display in the odometer. This will also verify the PCM is alive.

OK i did this and got a code for low charging ... assuming because i have cranked it dead a dozen times now ... so that would indicate my PCM is alive correct ?

 

[Animatedmean]

I did have this happen to me. I changed the CPS, no luck. Then changed the entire distributor, including Ckp, plugs, wires and coil - worked. No issues since

Yea i changed the coil rail and ive swapped it and plugs already for new ones ... no distributor on the 05 my 97 is a distributor so some changes im learning and working through

 

[JKP]

Yes, your PCM is alive and communicating.

The 05 and 06 PCMs are problematic though. More so if you have the AT.

The curious part is that you have spark but no bang with starting fluid.

Try disconnecting the cam sensor harness and see if it will fire. This will take a long crank as the computer will have to determine no cam sensor and then decide to batch fire the injectors and go into limp mode.

 

[Animatedmean]

Yes, your PCM is alive and communicating.

The 05 and 06 PCMs are problematic though. More so if you have the AT.

The curious part is that you have spark but no bang with starting fluid.

Try disconnecting the cam sensor harness and see if it will fire. This will take a long crank as the computer will have to determine no cam sensor and then decide to batch fire the injectors and go into limp mode.

Thanks ill give it a try in the morning. i randomly get a small chug like it may think about starting but nothing that i would expect. I pulled the coil ... ran a bar down the side grounded it and cranked it and all 6 had real good spark ... i even swapped the coil to one i had bought and same thing and can smell gas just no bang yet

 

[JKP]

One other possibility is that the timing may have jumped, but I would have thought that would have impacted the compression test.

Does it sound normal when it's cranking?

 

[Animatedmean]

One other possibility is that the timing may have jumped, but I would have thought that would have impacted the compression test.

Does it sound normal when it's cranking?

Yea cranking it sounds normal some times putters like it may want to start but never does ...I thought about timing also

 

[Painfultruth]

OK i did this and got a code for low charging ... assuming because i have cranked it dead a dozen times now ... so that would indicate my PCM is alive correct ?

Not exactly, you really need to put a code reader/scanner on it in order to make that determination.

 

[Animatedmean]

Not exactly, you really need to put a code reader/scanner on it in order to make that determination.

With a scanner it pulled the same code and I can read my vin

 

[Painfultruth]

With a scanner it pulled the same code and I can read my vin

Pull the cover off the oil pump drive and check the alignment with #1 cylinder at TDC

 

[JKP]

OK, one other thing that will cause this. An IAC that is stuck closed doesn't allow the engine to get any air. So the next time you try to crank it, press the gas pedal to slightly open the throttle. If it starts and runs, then dies when you release the gas pedal, the IAC is stuck closed.