EGR clogging

[doclees]

Fresh from the Ford dealer shop. I am told I am getting blow by causing my new EGR (from them - ouch!) to foul and give codes. I have no drivability issues and no significant oil use. Lots of power and get up and go.

What causes this condition besides worn rings? Will dirty oil rings? Can AutoRX help?
thanks

93 ATX with 161k

 

[projectSHO89]

The EGR nostrils on every SHO engine that has them will likely clog. If is not an issue with blow-by.

Try telling us the exact symptom you're trying to address. That way, you can figure out the likely problem and not have to deal with a Ford store if you don't want to.

Steve

 

[Fourcats]

We are getting EGR codes and have been swapping out smog "stuff" to see what changes {nothing yet}.

A VACUUM gauge hooked up to the intake will give you a good idea of "condition of the engine" {valves, rings, leaks, ect.} It should be between 17in & 21in of vacuum at warm idle.

 

[doclees]

Thanks Steve,
I bought this 93 from the mom of a Ford mechanic. He was unclear what was causing the light at the time. He did have TPS codes and O2 codes. I changed both with the TPS still coming up. He had just changed the TPS also. I assumed maybe a short or vacuum leak. I believe this car has a vacuum activated e-brake release that rarely works. I went to the folks that should be the experts. The dealer did not have any TPS or O2 codes but did have EGR codes and 71% vacuum or function. I don't remember. Said EGR was going bad. The cruise control takes a second or 2 to engage with a slight surge before locking in. Dealer could not get it to set at all and found problems in the clock spring and changed it. No change that I noticed but since this also works the air bag I'm not complaining about that work. Now they say the cruise is normal with that set time lag. They kept the car for 2 day cleaning out the clogged passages that 2 weeks ago said were not that bad when they changed the EGR. They are assuming/guessing that blow by is causing the clogging. No compression test was done. No charge for the cleaning and testing the second time. That was the right thing to do since I paid for a check engine diagnostic not a check engine guess. My faith in their effort is restored but my faith in their skill is still weak.

 

[naval-avi8or]

As many will tell you DON'T GO to FORD, most ford mechanics will look at you funny if you tell them you have a FORD SHO. I spent $$$$$$$$ at ford replacing and cleaning to have them fix nothing and just clear the codes. 10 miles from the stealership (not a typo) the light came back on. You need to remove your throttle body and clean out the passageways (nostrils) prior to spending any more on uneeded parts.

I have seen pictures I took floating aroound on the forum of my EGR nostrils after I cleaned them, so just do a search.

Out side of an annoying CEL I'm unaware of any problems that can result from driving with it plugged. Only ATX and California MTX's have the EGR system any way.

Good Luck

 

[Randall]

check out this link for a "how to" on cleaning the EGR passageways. It helped me get rid of my 332 code.

http://www.shoforum.com/showthread.php?t=7907&highlight=nostrils

 

[doclees]

Thanks guys, I went a whole day without the check engine light coming back on. Wow those ford guys realy know how to clean these passageways. Lets assume they are clear and I have a new EGR. What else should I check? That is what else after I check their work?

These are the original codes the dealer found 3 weeks ago before the new EGR and clock spring. 129,167,235,332.

 

[LeddZepp8687]

Well I had my runners put in a parts washing machine to get them really clean and then I took alof of carb cleaner with the runners all taken apart and used the air blasting nozzle on my air compressor to blow out the carbon plug that had formed in there, Literally, it was a black plug that blew out. Looks like you got yours solved quite a bit easier as mine required more work, But I have a spare sett of runners that I polished and and had ported.

 

[doclees]

Oh no LeddZepp I was joking. It came back on after only one day. They haven't fixed crap. Can I say crap? I checked the work order. It says there is oil in the DPFE which idicates blow by. Anybody buy that?

 

[projectSHO89]

Oh no LeddZepp I was joking. It came back on after only one day. They haven't fixed crap. Can I say crap? I checked the work order. It says there is oil in the DPFE which idicates blow by. Anybody buy that?

Nope.

The DPFE sample lines run from the exhaust to the sensor (via the EGR sample tubes.) You'd have to have a LOT of oil in your exhaust for any to make it to the sensor. I can't imagine any failure mode where this would happen and your engine would still run.

On my first SHO, my experience with the 332 code was that the EGR ports were clear, the problem was a faulty DPFE sensor.

The problem is not difficult to diagnose correctly.

Steve

 

[doclees]

Thanks Steve, I will persue that DX and let everybody know. Also do the code readers do anything more than what can be done with jumping the self dx and counting the check engine light flashes? Are they worth investing in?

 

[doclees]

Ok I changed the DPFE with a Autozone Wells brand. Still check engine light. I will check all passages for patency this week end. I went the new DPFE route first because Autozone said I could return it and it is easy to swap. The wife was doing about 20 miles of errands without it coming on. It usually takes highway speeds for a couple of minutes before it is triggered. I take it in to work today and there it goes. Now lets assume all passages are open, and that is a big assumption, what do I check next?

 

[projectSHO89]

The code scanners will not give you any additional data. The only ones that would be of benefit would be the ones that count and display the fast codes for you so don't have to count thge slow ones.

Perform the EGR "suck test". Short length od small vacuum line to the EGR valve. Engine idling. Suck on the line. Engine should stumble or die. If so, the ports are clear and the valve is operating. If not, either the ports are clogged or the valve is operating. Once removed, the valve can be inspected for mechanical operation.

If it passes the suck test and has a properly connected and operational DPFE sensor, I'd suspect the EVR solenoid or a loss of reference voltage to the DPFE sensor.

Steve

 

[doclees]

Thanks Steve, I will see if my SHO sucks this week end.

 

[naval-avi8or]

Thanks Steve, I will see if my SHO sucks this week end.

Don't suck to hard or you will crack the diaphram and ruin your EGR valve.
Only takes 7 psi of vaccumm.

 

[doclees]

Good thing I checked Naval. There are times my wife says I suck big time so this might have been an issue. Time a get a vacuum pump/gauge.

 

[greg geraci]

There right,
I took off my throttle body and stuck a piece of wire through the clogged nostrils. Codes cleared.