Check Engine and Codes, Need help!
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Senior User
Joined: Mar 2002
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From: Lone Star State
Check Engine and Codes, Need help!
Another check engine light, and this time not sure what to do. Need help from some of you Ford tech guys.
My OBDII codes are coming up as P0171 and P0174. Bank 1 and 2 lean.
The engine is jumping from 600-800 rpm's at idle.
Troubleshooting shows replacement of an o2 sensor, seems more like a vacuum problem, which i have no idea how to check properly unless someone has some input.
Replaced the plugs with oem's 10k ago. And replaced and EGR valve 4 months ago on the last check engine light.
Any help
Thomas
My OBDII codes are coming up as P0171 and P0174. Bank 1 and 2 lean.
The engine is jumping from 600-800 rpm's at idle.
Troubleshooting shows replacement of an o2 sensor, seems more like a vacuum problem, which i have no idea how to check properly unless someone has some input.
Replaced the plugs with oem's 10k ago. And replaced and EGR valve 4 months ago on the last check engine light.
Any help
Thomas
Mountain Pass
Joined: Jan 2004
Posts: 210
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From: Ixonia, WI
Correct me if I'm wrong guy's but I would clean the Mass Airflow Sensor in the air intake tube. You may have to replace it if it is bad enough but I would try to clean it first with some electronic cleaner. Ther may be some crap on it goofing up the amount of air flow sensed for the computer. It happend to a freind of mine after taking his Escort in for a coolant change. (even the same codes) I took a look at the MAF and found the mechanic somehow spilled a bunch of coolant on it. Cleaning it took care of the problem. Do you have a K&N filter in your truck? Sometimes they can shed any extra oil and it lands on the MAF. Good Luck
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Senior User
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From: Lone Star State
I do have a k&n cold air in it, I checked it and it seems to be ok. I replaced the fuel filter this morning and it is still doing the same thing.
I am going to look at all my vaccum lines again and double check.
I am going to look at all my vaccum lines again and double check.
Post Fiend
Joined: Jun 2003
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From: NE Texas
On the outer side of the throttle body (towards the front of the truck) there is a cheap 90 degree ell that leads to the PCV valve on the passenger's side of the engine. That ell becomes soft, real soft, and fails under load.
Have you checked that? Also check for a vac leak at the PCV valve and other vac tubes.
Have you checked that? Also check for a vac leak at the PCV valve and other vac tubes.
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Senior User
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From: Lone Star State
B-orn, That ell is it the lower or upper hose comming out of the throtle body. There are two 90 degree hoses coming out of the housing and leading back towards the pcv. Too hot to get back there now, but i can see what u are talking about.
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Originally Posted by T_Moss
I do have a k&n cold air in it,
A second-rate K&N, a technological relic of the '50s will kill a MAF in short order; resulting in the predictable symptoms you are experiencing.
1. Get rid of the K&N crap and install a proper OEM filter;
2. Attempt to clean the MAF with throttle-body cleaner; and if the K&N has contaminated the MAF to the point that it's beyond cleaning;
3. Get a new MAF.
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Post Fiend
Joined: Jun 2003
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From: NE Texas
Originally Posted by T_Moss
B-orn, That ell is it the lower or upper hose comming out of the throtle body. There are two 90 degree hoses coming out of the housing and leading back towards the pcv. Too hot to get back there now, but i can see what u are talking about.
It's about 3/4" diameter (outside diameter). You can't look at it and tell that it's bad, but once you put your fingers on it, and it feels like chewed bubble gum (soft), then that's a good sign. It will collapse when the engine calls for more vac.
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From: Colville
I don't think there is a problem with the K&N filters, just their brand of filter oil. I use PJ1 foam filter oil sold at motorcycle shops. It is much sticker than K&N oil and won't get sucked into your intake track.
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From: Lone Star State
I have two hoses comming out the side and the pcv hose out the center directly under the billet. I thought you were taling about the two on the passanger side. Turns out it was the pcv hose. I felt around and was the elbow portion, it had a hole in it. Hard sucker to get to, had to take my throttle assemble apart to get the new one on. It runs like a kitten now.
Thanks for the help.
Thanks for the help.
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Senior User
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From: Lone Star State
I just took my positive cable off the battery and let it sit for 10 minutes and it will reset the pcm and the check engine light will go off. Or u can take it to autozone and they will reset it for u for free.
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Joined: Nov 2003
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Good afternoon I know that this issue has come up before. I followed the same hose on my truck and found that the hose was in two parts. The elbow has a snap in hose that run over to the PCV valve. As i was following the hose it didn't feel right. I put one hand on the elbow and pressed lightly on the hose and herd a snap. I did the remove the battery terminal trick and turned the light out. I then pulled my 5 wheel home over the mountains and the light did not come back on. Is that two peace hose normal or has someone changed it?
Post Fiend
Joined: Jun 2003
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From: NE Texas
Originally Posted by oldscout
Is that two peace hose normal or has someone changed it?
The hose seems to be made of better material than that elbow.
Somebody ought to have to eat that elbow material design - blueprint (or toilet tissue) whatever it was drawn up on.
