Issues with Idling after sensor replacement

[scorpo8972]

Hey, I had my Service engine soon light on and it was the P0401 Code, low air flow detected In EGR. Went to Partsource 3 weeks ago, they said it was the EGR Valve itself(i found that strange since EGR'S are mechanical and rarely ever fail. Well I installed it and that did't work at all. The other option is instead of mechanical it could be a bad EGR Vacuum Solenoid. When I replaced it yesterday night(July 21) and made sure all 3 cables where plugged in, and MAF sensor plugged back in(must remove air box to get at the EGR Solenoid). I started it, ad let it idle, I then noticed the weird shaking and felt light the truck was going to stall(rpms were also at 650ish instead of 850ish. The truck was runig perfectly fie with EGR inoperative, so now why is it idling like this. PLZ reply ASAP, I'm out of a vehicle now since I wo't drive it like that.

 

[JW]

Double-check all your vacuum lines. There are a few haunting around the EGR area.

 

[scorpo8972]

Hey i did triple checks and nothing, all hoses are in good shape and all are inserted properly. The only thing I can think of is a clogged cat, however even then my truck was running fine so why the change? And I'm not going to a shop, they'll charge me hundreds for BS just to take my hard earned cash.

 

[matt0248]

Put the old vacuum solenoid back in and see how it runs. Usually a P0401 is set due to a failed DPFE Sensor which actually measures the flow in the EGR system. They are very inexpensive and easy to replace.

 

[kkjb4x4.0]

Put the old vacuum solenoid back in and see how it runs. Usually a P0401 is set due to a failed DPFE Sensor which actually measures the flow in the EGR system. They are very inexpensive and easy to replace.

What he said,,partsource eh?You took his advise?

 

[scorpo8972]

I went back and had the egr valve exchanged and installed it there, we started it up, still the same problem. Then we exchanged the solenoid, and it fixed the stuttering and low rpm problem. The two egr solenoids were exactly the same except that the electrical prongs were gold plated(just like my old one) so we figured the BWD guys put the wrong part into the wrong box. Two days ago I broke my gas cap when it rolled off my roof while I was pumping gas >.< Got the "Service Engine Soon" light back on with the code P0401. The guy asked when was the last time you filled and I said last night, however my gas cap is busted and he stated that a broken gas cap would cause that sometimes(I went ahead and replaced it since the old one was split in two anyway). Today the light came back on after picking my bro up, when I parked in my garage I couldn't shift into park(so I was like is this a new code linked to another problem), later I find out my Brake light switch is inoperative(evidence is the brakes lights did not go on when surpressed). They also checked the code again and guess what the EGR code is still on >.< I checked all vacuum lines, the intake, the throttle body gaskets, etc and still can't figure it out. My exhaust manifold has a small hole in it, so would that cause it? I'm stumped :S

 

[matt0248]

DPFE sensor. $20 or $30 bucks. this is usually the cause of the P401.

 

[scorpo8972]

DPFE sensor. $20 or $30 bucks. this is usually the cause of the P401.

Yeah I was suspecting that at start but my cat makes squeaks when starting up so I thought can't be the sensor. I think I also have a slightly clogged cat too. Is there stuff I can use to clean it out, like something you spray into the intake? Thanks.

 

[trucku]

Yeah I was suspecting that at start but my cat makes squeaks when starting up so I thought can't be the sensor. I think I also have a slightly clogged cat too. Is there stuff I can use to clean it out, like something you spray into the intake? Thanks.

I have read you can clean your combustion chamber and exhaust system with water. Your truck sucks up water into intake via vacuum line, as you would with seafoam. It is almost the same procedure, except there is no stopping the engine until your exhaust stops expelling a lot of steam and water. Your engine will basically steam clean the combustion chamber and cats.

Watched a bunch of youtube videos and did a lot of reading about it.

The procedure takes a long time since you are running a lot of water slowly through the intake. I did this two times. I Used a half gallon the first time and my exhaust expelled very dirty water the whole time. I used a clear medical tube (1/4 od) as a intake hose for the water. I connected that to the vacuum line I was using into the intake. The clear hose is great for metering how much water you are sucking in. Second time I used another half gallon of water. By the time I was done, the water exiting from the tailpipe was completely clear.

I do feel that the truck is running better after this.

Note: the clear medical tubing's diameter is small enough that it didn't affect the idle of the truck too much when it was not sucking in water. Also I performed the first procedure at idle and the second with the engine at about 1500 to 2000 rpm.

From what I have read, cleaning the combustion chamber and exhaust system of carbon this way is old school, just like bypass filters.

Oh another thing to think about, more is less in this case. Too much water can hydro lock your engine. So don't put a hose to your throttle body...Be patient. The procedure takes long.

Do your research before trying this.

Here is one vid

http://www.youtube.com/watch?v=jWqN8pBHJhE

How this guy does it is risky in my opinion.
http://www.youtube.com/watch?v=bv4a3k-6Z4w&feature=related

It addition, performed the cleaning on my wife's 2000 crv and I swear it sounds quieter. Maybe just in my head. I ran a gallon through her truck.
Good luck
Vishant

 

[scorpo8972]

I have read you can clean your combustion chamber and exhaust system with water. Your truck sucks up water into intake via vacuum line, as you would with seafoam. It is almost the same procedure, except there is no stopping the engine until your exhaust stops expelling a lot of steam and water. Your engine will basically steam clean the combustion chamber and cats.

Watched a bunch of youtube videos and did a lot of reading about it.

The procedure takes a long time since you are running a lot of water slowly through the intake. I did this two times. I Used a half gallon the first time and my exhaust expelled very dirty water the whole time. I used a clear medical tube (1/4 od) as a intake hose for the water. I connected that to the vacuum line I was using into the intake. The clear hose is great for metering how much water you are sucking in. Second time I used another half gallon of water. By the time I was done, the water exiting from the tailpipe was completely clear.

I do feel that the truck is running better after this.

Note: the clear medical tubing's diameter is small enough that it didn't affect the idle of the truck too much when it was not sucking in water. Also I performed the first procedure at idle and the second with the engine at about 1500 to 2000 rpm.

From what I have read, cleaning the combustion chamber and exhaust system of carbon this way is old school, just like bypass filters.

Oh another thing to think about, more is less in this case. Too much water can hydro lock your engine. So don't put a hose to your throttle body...Be patient. The procedure takes long.

Do your research before trying this.

Here is one vid

http://www.youtube.com/watch?v=jWqN8pBHJhE

How this guy does it is risky in my opinion.
http://www.youtube.com/watch?v=bv4a3k-6Z4w&feature=related

It addition, performed the cleaning on my wife's 2000 crv and I swear it sounds quieter. Maybe just in my head. I ran a gallon through her truck.
Good luck
Vishant

Hey, that sounds like a good idea but one issue is Im in an underground garage so kinda hard espeacially with new management how decided to fancy up the underground and don't what as diyers doing anything with fluids(ye even h20). Thanks anyway I'll probably use seafoam since it's the only thing I can do. I also fixed the problem, faulty brand new sensor(someone at the factory put wrong one in wrong box). Looks identical but the contacts were 1mm longer and they were grey, my originals were gold plated so I got a new one which fixed idling issues. However that didn't fix the problem. The DPFE which my gut feeling told me from day one of the service engine light was the problem it was faulty. I did get money back for egr, but solenoid was a no since it was electrical, not to mention the ****y stock seized bolts broke the bolt insert(cheap plastic). Though it was $30 dollars, in Canada prices are usually 50-170 percent inflated compared to America even though are dollar is on par with the american dollar. I paid $67 dollars at partsource(cheapest but great parts place). I also had to buy replacement tubing since the originals actually melted onto the metal pipe(only 8 bucks for a foot at ford). Truck runs great except that annoying exhaust leak from the exhaust manifold # 8 cyl outake. Well thanks for the help everyone. Now if only soemone could help me with figuring out how my first row dome comes off, my haynes manual shows the version w/o a sunroof but I have one so its useless.