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-   -   egr valve failure with no codes? (http://www.jeepgarage.org/f187/egr-valve-failure-with-no-codes-41357.html)

05rockymountain 04-27-2012 10:56 PM

on my 05 wk,4.7 I am getting the elusive hesitation/stumble/on light throttle pressure when cruising at speeds under 80 km/hr.seems like slight ign miss ,with constant throttle it seems to have a slight surge up and down at lower speeds below 90,also exhibits an intermittent high idle (700-750 rpm compared to usual 500-550 rpm)and also sometimes at normal idle it is slightly rough(can feel slight shake in veh)other times its smooth as silk,with hvac on or off eliminating compressor load,today i exhibited another symptom on startup cold,i started jeep ,it died when i went into gear ,then it cranked over 3 times as long to start,after starting it went to 700-800 rpm and wouldnt come down for a few minutes(temp 10 celcius,seems to be getting progressively worse ,a few times at 80 k when taking foot of gas it bucked a bit almost like torque converter clutch not disengaging)i can also hear a hiss by egr valve,not quite a vac leak hiss ,more like air rushing noise.at speeds 100 km/hr plus ,it seems perfect. i have replaced plugs,cleaned iac and port,killed all the mosquitos in my neihborhood with seafoam,lol,cleaned tbody,ran seafoam through fuel tank and oil,tried different grades of fuel,replaced tps,i have an obd II scanner and no codes are present and i have never seen a "check engine" light come on ,it seems like a possible egr concern in my guess from symptoms but it in my view should set codes as dpf sensor monitors this,has anyone had egr failure with similar symptoms with no codes?,i have not had software updates yet but jeep has 140000 km on it ,if software was needed i would think it would have had issue before now
I may just go to steeler tomorrow and get updates done ,but I still am guessing egr leak /sticking open.sorry for the long post but the more details the better in this problem,any ideas from the wk brotherhood?

NikonKiem 05-22-2012 10:02 AM

I'm having the same issue? But my check engine light does come on. I have replaced the fuel pump, the injectors and the spark plugs and still having the issue. But at least cuts happening less. Please let me know what the stealership says.

dr.lee.baugh 05-22-2012 01:24 PM

Re: egr valve failure with no codes?
 
Quote:

Originally Posted by 05rockymountain (Post 620490)
on my 05 wk,4.7 I am getting the elusive hesitation/stumble/on light throttle pressure when cruising at speeds under 80 km/hr.seems like slight ign miss ,with constant throttle it seems to have a slight surge up and down at lower speeds below 90,also exhibits an intermittent high idle (700-750 rpm compared to usual 500-550 rpm)and also sometimes at normal idle it is slightly rough(can feel slight shake in veh)other times its smooth as silk,with hvac on or off eliminating compressor load,today i exhibited another symptom on startup cold,i started jeep ,it died when i went into gear ,then it cranked over 3 times as long to start,after starting it went to 700-800 rpm and wouldnt come down for a few minutes(temp 10 celcius,seems to be getting progressively worse ,a few times at 80 k when taking foot of gas it bucked a bit almost like torque converter clutch not disengaging)i can also hear a hiss by egr valve,not quite a vac leak hiss ,more like air rushing noise.at speeds 100 km/hr plus ,it seems perfect. i have replaced plugs,cleaned iac and port,killed all the mosquitos in my neihborhood with seafoam,lol,cleaned tbody,ran seafoam through fuel tank and oil,tried different grades of fuel,replaced tps,i have an obd II scanner and no codes are present and i have never seen a "check engine" light come on ,it seems like a possible egr concern in my guess from symptoms but it in my view should set codes as dpf sensor monitors this,has anyone had egr failure with similar symptoms with no codes?,i have not had software updates yet but jeep has 140000 km on it ,if software was needed i would think it would have had issue before now
I may just go to steeler tomorrow and get updates done ,but I still am guessing egr leak /sticking open.sorry for the long post but the more details the better in this problem,any ideas from the wk brotherhood?

This certainly could be the EGR valve - I (including many others) have had similar symptoms without any codes being thrown that were solved by replacing the EGR. If you do it yourself it is a fairly cheap replacement, and may solve things completely. I also have had a crankshaft sensor go kind of funny and resulted in a similar cranking without starting/erratic idling/surging and pulsing sort of deal. This was also a cheap and straightforward DIY job.

Of course, this was on a hemi, not sure how much of it applies to your 4.7...but as a simple answer, I would say yes - it is possible to have an EGR issue and not throw the CEL.

dr.lee.baugh 05-22-2012 01:27 PM

Re: egr valve failure with no codes?
 
Quote:

Originally Posted by NikonKiem (Post 633165)
I'm having the same issue? But my check engine light does come on. I have replaced the fuel pump, the injectors and the spark plugs and still having the issue. But at least cuts happening less. Please let me know what the stealership says.

What codes are being thrown?

NikonKiem 05-22-2012 02:40 PM

I would go off within 5 minutes of turning on.

dr.lee.baugh 05-22-2012 02:54 PM

Re: egr valve failure with no codes?
 
I believe if a code is causing the engine light to come on, even if it turns off there will still be a record of it in the PCM. Not sure if the key dance will pull stored codes, but most OBD scanners will be able to retrieve this information.

NikonKiem 05-22-2012 06:35 PM

I used my superchip to check and it said that no codes were present, but I'll do the key dance and check

05rockymountain 05-24-2012 07:10 PM

Re: egr valve failure with no codes?
 
replaced egr valve and corrected 80 % of issue ,have not gotten tsb for converter lock up done yet. but thats next to get done ,just serviced transmission and also corrected delayed engagement.although its always something with my wk i actually dont mind working on it ,most things are easy to get at ,even egr valve wasnt bad ,just need good collection of deep and shallow sockets and a few different lengths of extensions. trans service was easy too. one thing i have also noticed is that there are a lot of changeup parts from chrysler on my model ,before i buy aftermarket parts i always check if chrysler changed them up ,stabilizer bushings,new bracket and bushing design,trans filters ,sump and spin on have changed up a few times.

NikonKiem 05-24-2012 09:58 PM

I may have to do that next. Mine threw a code today and I was able to check it. http://img.tapatalk.com/c6e4eb5b-f55a-2a99.jpg. I have no clue what this means.

05rockymountain 05-25-2012 10:36 AM

Re: egr valve failure with no codes?
 
I think you may have another concern ,I would check the tps ,wiggle the connector at the tps and see if idle fluctuates at all ,tps can also set some false codes,they arent that expensive ,less than 100 bucks and 5 min change ,i have replaced mine
,you might also want to try a update on pcm from dealer ,it wont hurt and the updates can only be beneficial. before you replace a bunch of parts.

dr.lee.baugh 05-25-2012 12:36 PM

Re: egr valve failure with no codes?
 
I believe that code relates specifically to the injector on the #8 cylinder.

You could visually inspect the wires, unplug and plug back in the injector - see if that solves things.

If not, you can try moving that injector to another cylinder to see of the trouble code follows. If it does, you know the injector is going bad.

I do not know of the other conditions that could perhaps throw this code...quickly looking at the wiring diagram for the circuit doesn't show a whole lot of systems in between that could cause erroneous behavior (a couple of fuses, the ASD relay, power distribution center, PCM, and injector itself).

My guess is either a short somewhere in the wiring or the injector is no good.

NikonKiem 05-25-2012 04:46 PM

I'll try the tps when I get home, and I have been avoiding the PCM update because I don't want to pay for it lol. As for the injectors 2 were clogged so I has them replaced over a month ago.


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