94 f150 5.0 runs rough at low throttle - F150online Forums

Go Back  F150online Forums > Powertrain & Mechanical > V8 Engines
94 f150 5.0 runs rough at low throttle > 94 f150 5.0 runs rough at low throttle

94 f150 5.0 runs rough at low throttle


Old 06-05-2012, 10:55 PM
Junior Member
Thread Starter
Join Date: Jun 2012
Posts: 8
94 f150 5.0 runs rough at low throttle

guys I'm new and have a question. I've looked through the forum but can't seem to find an answer so here goes. I just put a reman engine in my 94 f150. Engine runs good while acclerating but a little rough at cruise. I've pinpointed down to the EGR system but can't figure out what is happening. It seems that the EGR valve is staying open too long. I can unplug the valve and it runs fine. I've replaced the valve and the EGr solenoid but it still does it. You can slowly throttle up and the engine shakes like it's skipping but with the valve unplugged it revs up fine. Any ideas?
Reply With Quote
Old 06-08-2012, 12:27 AM
Join Date: Jul 2006
Location: Las Cruces, NM
Posts: 56
Excellent question! I wish I had an excellent answer for you. But......and I'm no expert by any means.....

This is what I have heard and understand about the EGR valve. The valve directs a small portion of exhaust gasses back into the inlet air charge and lowers the maximum temperature of the burning fuel. The valve then makes sure that the EGR system is off at idle, where it would lead to erratic and loping idle, as well as at full throttle, since adding exhaust gasses robs power from the engine. Therefore, maybe the valve is staying open??? Possibly the ECM is telling it to stay open? Have you checked your O2 sensors? Could there be a vacuum leak? Keep the EGR valve unplugged? I think I might be I'm shooting in the dark, but no one else has replied and didn't want you think we didn't care. If this doesn't help you, I hope you find the answer soon. These things can be a pain the butt. I wish you the best of luck!

If you figure it out...please let me know what the culprit was.
Reply With Quote
Old 06-08-2012, 06:20 PM
Junior Member
Thread Starter
Join Date: Jun 2012
Posts: 8
Thanks for the reply. It's an odd situation for sure. What happens is when you crack the throttle just above idle it seems that the engine is skipping. There is no check engine light. Once you start to rev it smooths out and runs fine. The problem is when you are cruising down the road that is about where the throttle ends up and causes that same skip feeling. It's almost like when you put a small amount of vacuum on the EGR at idle how it lugs the engine down. I will definitely let you know if I figure it out.
Reply With Quote
Old 06-10-2012, 01:00 AM
Senior Member
Join Date: Jun 2011
Location: Houston,Tx
Posts: 439
try a search for egr to see if you can more info on site. Also check the dpfe valve on your egr system

Last edited by K.R.newbie; 06-10-2012 at 01:07 AM. Reason: more info
Reply With Quote
Old 08-18-2012, 09:39 PM
Junior Member
Thread Starter
Join Date: Jun 2012
Posts: 8
I'm still muckin with this issue. With the EGR disconnected there is a slight vibration around 1500 RPM but when I connect the EGR it gets alot worse. I have looked for a vacuum leak but can't seem to find one. Any ideas? This is driving me crazy. It wasn't doing this before the engine change which makes me wonder if something was hooked up wrong.
Reply With Quote

Related Topics
Thread Starter
Last Post
2015 - 2018 F-150
07-11-2017 11:47 AM
2015 - 2018 F-150
08-04-2016 04:07 PM
V8 Engines
10-08-2015 11:15 PM
pa 150
2004 - 2008 F-150
07-19-2015 07:57 PM
1997 - 2003 F-150
07-10-2015 11:04 PM

Thread Tools
Search this Thread
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


All times are GMT -4. The time now is 11:26 AM.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
  • Ask a Question
    Get answers from community experts
Question Title:
Your question will be posted in: