04 Durango 5.7 Hemi Issues
Thread Starter
|
Amateur
Joined: Jul 2010
Posts: 33
Likes: 0
BLK:
Sorry to hear this issue is a stubborn one for you.
I know that the 5.7 engine does not have a TPS per say as the TB also performs this function. I believe it also performs the IAC function as well.
If you have swapped in a known good one, I think you can rule those out.
A clogged or bad converter usually affects the engine most while under load in the upper RPM ranges.
Unless it is totally clogged, the engine should idle fine. Disconnecting the exhaust is one way of ruling them out.
An easier way to diagnose a restricted exhaust is to attach a vacuum gauge to the engine, and then run the engine into the 3-4K RPM range.
An engine with a proper exhaust system will initially have the vacuum drop at first, but will then recover and build.
A restricted system will show the vacuum drop and then stay down due to the restriction.
The engine will generally lack power in the upper range as well.
What fuel pressure readings did you see? Were you able to get some readings with the engine under load?
Don
Sorry to hear this issue is a stubborn one for you.
I know that the 5.7 engine does not have a TPS per say as the TB also performs this function. I believe it also performs the IAC function as well.
If you have swapped in a known good one, I think you can rule those out.
A clogged or bad converter usually affects the engine most while under load in the upper RPM ranges.
Unless it is totally clogged, the engine should idle fine. Disconnecting the exhaust is one way of ruling them out.
An easier way to diagnose a restricted exhaust is to attach a vacuum gauge to the engine, and then run the engine into the 3-4K RPM range.
An engine with a proper exhaust system will initially have the vacuum drop at first, but will then recover and build.
A restricted system will show the vacuum drop and then stay down due to the restriction.
The engine will generally lack power in the upper range as well.
What fuel pressure readings did you see? Were you able to get some readings with the engine under load?
Don
The converter and fuel pressure seems good. I replaced the MAP sensor and still the same issue. Maybe EGR or crankshaft sensor?? Suggestions??
Thread Starter
|
Amateur
Joined: Jul 2010
Posts: 33
Likes: 0
UPDATE: I replaced the EGR valve and nothing. I removed the oil cap and now it stays on without gas but idles rough. If I put the oil cap back it sounds like suctioning and it dies.. recommendations?? Cracked intake manifold?
Thread Starter
|
Amateur
Joined: Jul 2010
Posts: 33
Likes: 0
Yes. it stays on but idles rought (without power) without the intake hose hooked to the TB and without the oil cap. If I pu the oil cap dies. Was also told maybe PCV valve??
Thread Starter
|
Amateur
Joined: Jul 2010
Posts: 33
Likes: 0
There is pressure sucking in from the oil cap..
Record Breaker
Joined: Nov 2006
Posts: 1,222
Likes: 1
From: Ohio
BLK:
I believe the sucking or vacuum you are seeing at the oil fill cap is from the plastic line running from it over to the air box.
I would think you would have a Pcode stored in the system if the crank sensor was flaky.
Have you run a compression test at all? You may have valve spring issue in the making that is causing the rough running.
Dont recall you ever saying how many miles on the D? Being an 04, the valve issue is a very real possibility.
What is the build date on it?
Don
I believe the sucking or vacuum you are seeing at the oil fill cap is from the plastic line running from it over to the air box.
I would think you would have a Pcode stored in the system if the crank sensor was flaky.
Have you run a compression test at all? You may have valve spring issue in the making that is causing the rough running.
Dont recall you ever saying how many miles on the D? Being an 04, the valve issue is a very real possibility.
What is the build date on it?
Don
Last edited by n8ech; Apr 30, 2012 at 08:05 PM.
Thread Starter
|
Amateur
Joined: Jul 2010
Posts: 33
Likes: 0
BLK:
I believe the sucking or vacuum you are seeing at the oil fill cap is from the plastic line running from it over to the air box.
I would think you would have a Pcode stored in the system if the crank sensor was flaky.
Have you run a compression test at all? You may have valve spring issue in the making that is causing the rough running.
Dont recall you ever saying how many miles on the D? Being an 04, the valve issue is a very real possibility.
What is the build date on it?
Don
I believe the sucking or vacuum you are seeing at the oil fill cap is from the plastic line running from it over to the air box.
I would think you would have a Pcode stored in the system if the crank sensor was flaky.
Have you run a compression test at all? You may have valve spring issue in the making that is causing the rough running.
Dont recall you ever saying how many miles on the D? Being an 04, the valve issue is a very real possibility.
What is the build date on it?
Don
