Hesitation around 35mph!! Vacuum leak?

[raptor125]

Okay, so I got a 95 Explorer Sport 4x4 with a 4.0 engine. I have owned it for about 6 or so months now and it has been really great to me. But recently it has started to hesitate around 35mph. The check engine light started to come on and I went ahead and pulled the codes by jumping the OBDI connector etc to make the check engine light blink at me. Well from my understanding it was the EGR valve. I went ahead and replaced the EGR valve thinking that should solve the problem. Well the old one was pretty nasty so it didn't hurt to replace it anyhow. Well it ran great for about a day and then I took it out today and it started to do it again. I dropped some fuel injection cleaner in it after a fillup and ran it on the highway. It runs perfect at 70mph or higher, but when I get off the highway and into town driving the check engine light will come back on and it will start to hesitate in lower speeds. Not bad, but you can notice it. Engine seems to run fine during idle, and also when under a load. So what the heck could be wrong? When driving it, I think I can hear a whistling noise from under the hood, but that could be anything. So I thought maybe a vacuum leak. Any ideas? I would like to get this thing fixed because I am moving soon and need to drive this thing 2,000 miles. Don't want anything to happen, thanks!

 

[Tbars4]

....what is the new code you are getting??? :scratch:

 

[BrooklynBay]

It could be a number of things, such as bad vacuum lines, IAC, MAF, intake gaskets, or the DPFE sensor. This is why code numbers are so important. It helps you troubleshoot the problem instead of blindly replacing parts which might still be in good condition.

 

[raptor125]

When I ran the codes before I replaced the EGR valve I got this:

3 3 2

3 2 7

That is the best I could get out of it. That is the number of times that the check engine light blinked. My books tells me this when I look the 332 and the 327 code up:

327 - EGR Valve Pressure Transducer/Position Sensor circuit below minimum voltage

332 - EGR valve opening not detected

Now since I put the new EGR vavle in, I haven't ran the check engine codes again. I was afraid that the old codes were still gonna be there plus news ones. Should I go ahead and pull codes again? And did I read the codes wrong?

 

[Tbars4]

...you need to give us the current codes...

 

[raptor125]

Okay, I shall pull the codes sometime today and get them posted here. Hopefully these shall give me a clue on what is going on.

 

[raptor125]

Okay, pulled the codes again and this thing is really starting to make me wonder wtf is going on. They were the same as last time. So either I read them wrong, and didn't solve the problem or there is more wrong here then I thought. Anyhow the lights blink like this: 3 3 1 3 2 7 3 3 2 3 2 7 3 3 2

How would I read this? Maybe I have been doing this wrong. Any thoughts?

 

[Tbars4]

...you read the flashes between the short pauses...the long pause comes and you get another code....i am not all up on egr electrical but you have a problem with that item or it's wiring...
...did you do an advanced search on here for egr??? it will probably lead you to a fix...good luck...

 

[5.0ExplorerMan]

Clean the MAF sensor and give it a drive. It could possibly be the MAF. You say at idle...no problems, and when doing 70mph...no problems. My truck seemed to have a HP issue when in 2nd gear, which would be around 35mph. I cleaned the MAF and immediately noticed HP gains , better throttle response, and better gas mileage. May take a few drives to get the air/fuel ratios correct in the computer, but you should notice the changes within a few days for sure. Try it out...can't hurt with a bottle of CRC Mass Air cleaner running about $7. If the problem gets fixed and then starts up again within a few weeks, you may have to replace the MAF sensor all together.