Running too rich?

[Action Matt]

Hello all, my 91 bronco has encountered anotehr issue.

Last night I started it up and it revved really high and I could smell gas as I was driving. This morning I started it up, went to class and returned home. It was idling funny and I could smell gas as I drove. I was home for an hour and had to leave again to go to work, but this time it wouldn't turn over. The spark is there and the fuel rails were pressurized. When I got home from work I went to toy with it and it started up, however it still idled badly and smelled of gasoline. Also the exhaust was usually thick.

Did my truck start running too rich or could it be a bigger issue?

Thanks in advance.

 

[Bronk351]

Does it smoke on a startup?

 

[Seabronc]

The mixture is computer controlled in your truck. Something is making the computer think it is running lean. A good candidate for that is the O2 sensor. Check to see if you have any stored codes.

Good luck,

>-

 

[BroncoJoe19]

To pull Diagnostic codes all you need is a short piece of wire and the ability to count to ten.

Here is an instructional thread on how to pull codes.

http://broncozone.com/forums/index.php?s=&...ost&p=74581

Also as SeaBronc mentioned your computer thinks the truck is running lean. OFten that is casued by a vacuum leak, or unmetered air getting into the system after the MAF sensor. SInce I don't think a '91 has a MAF sensor, it is even more likely that it is a vacuum leak. Prior to pulling codes you should check for and verify that there are no vacuum leak(s). A portion of the above thread is dedicated to helping you find any leaks.

Let us know how you make out.

joe

 

[Action Matt]

Alright, thanks for the responses. I'll have to check the vaccuum lines tomorrow. It does smoke on startup and still smells of gasoline whenever it's running.

 

[BroncoJoe19]

WHat about pulling codes?

That'll help point to the O2 sensor that Seabronc mentioned.

 

[Shadow_D]

I had a similar problem with my 1990 last year and I found the problem to be a bad fuel pressure regulator... I replaced it and it seems to be running fine now.

I had also noticed the motor sounding like it kinda had a "wet" sound, hard to describe, but that is now cleared up.

Pull the codes and see where that points you...