> > Register < <ForumsActiveProfileSearchFAQ
Username:
Password:
Save Password
Forgot your Password?

 All Forums
 Truck Related
 Fuel Systems
 88 f-150 rough idle - any ideas?

ReplyActiveNew TopicPrint
Author  Message Next Topic  

britor305
Member

Blogs: 0 (Add)
Vehicle: 2rangers,2 f150s
Joined: Jul 2009
Member # 5775
From: Palm Bay florida

Posted - July 5 : 11:36p Reply with Quote Report this post to a moderator
rough idle when first starts up. acts like it wants to shut off but it gets better when you give it gas. 5spd . doesnt have good pick up anymore. it putters sometime and gives up idleing.

ive replaced the egr valve and position sensor, oil and filter, plugs and wires, throttle position sensor, air filter, and idle air control valve.

any ideas?


Check out the latest parts and accessories from Truck Hownd

Carnival Freak
Turbocharged Member

Premium Member

Blogs: 0 (Add)
Vehicle: 2007 2500HD, 2006 KTM 450
Joined: Apr 2007
Member # 2681
From: South OC CA
Visit Gallery

Click to view gallery

Posted  - July 5 : 11:49p Reply with Quote Report this post to a moderator
How about the Oxygen Sensor?

britor305
Member

Blogs: 0 (Add)
Vehicle: 2rangers,2 f150s
Joined: Jul 2009
Member # 5775
From: Palm Bay florida

Posted  - July 5 : 11:51p Reply with Quote Report this post to a moderator
not yet, is there any way to check that? i figured the o2 sensor would trigger check engine code.

Tom in Tacoma
King of the Forums!

Premium Member

Blogs: 0 (Add)
Vehicle: Truck? What truck?
Joined: May 2005
Member # 9
From: Over yonder WA
Visit Gallery

Click to view gallery

Posted  - July 6 : 2:38p Reply with Quote Report this post to a moderator
I'll wager a fair amount of money that you've got a vacuum leak somewhere. They often show themselves by a really rough idle. Might even get a bit better as the engine warms up?

Check out all the vacuum lines as well as listening for a whistling sound around the intake manifold, throttle body and heads.

I'll be waiting here to see if I was right. Go on now - go check!

Mort
Nitrous Member

Premium Member

Blogs: 0 (Add)
Vehicle: 2009 F-150 XL
Joined: May 2005
Member # 86
From: Mortville WA
Visit Gallery

Click to view gallery

Posted  - July 7 : 7:54a Reply with Quote Report this post to a moderator
I had to say it, but Tom is probably right. Bad thing is, those things have about eight miles of vacuum hose.

Tom in Tacoma
King of the Forums!

Premium Member

Blogs: 0 (Add)
Vehicle: Truck? What truck?
Joined: May 2005
Member # 9
From: Over yonder WA
Visit Gallery

Click to view gallery

Posted  - July 7 : 10:57a Reply with Quote Report this post to a moderator
Quote:
Originally posted by Mort

I had to say it, but Tom is probably right. Bad thing is, those things have about eight miles of vacuum hose.

britor305
Member

Blogs: 0 (Add)
Vehicle: 2rangers,2 f150s
Joined: Jul 2009
Member # 5775
From: Palm Bay florida

Posted  - July 7 : 1:20p Reply with Quote Report this post to a moderator
i had a buddy check and he said vacuum is right on . i looked for leaks . sooooo many hoses on this truck but i checked them ALL and nothing .

MrSVTGal
Supercharged Member

Blogs: 0 (Add)
Vehicle: 2000 Ford Expedition
Joined: May 2005
Member # 5
From: South OC CA
Visit Gallery

Click to view gallery

Posted  - July 8 : 2:44a Reply with Quote Report this post to a moderator
There's a BIG vacuum tree under the upper intake, if you have the intake that sort of folds over to the side (like a 5.0 Mustang, but the other direction, if I remember right). It's easy to have a leak under there that's not obvious. Spray a little WD-40 or carb cleaner in that general area when it's idling rough, and if you have a leak the idle will change (probably smooth out for a moment) as the stuff gets sucked into the intake.

Also, check the big line that runs to the master brake cylinder vacuum reservoir. There's usually a flimsy plastic check valve along with a big fat vacuum line - lots of junctions where you could get a leak.

Have you checked that all the upper and lower intake bolts are at least snug? (none of them get torqued all that much, but when the gaskets shrink with age they can end up 'loose').

MrSVTGal
   Message Next Topic  
ReplyActiveNew TopicPrint
 
                               
                                       
Please visit our supporting sponsors. Advertise here!