This is driving me nuts !

[reags8]

Well I've replaced the t-stat and removed my intake, cleaned it and replaced any suspect vacuum lines (ie if they were noticiable worn or cracked or just "looked" old). Re-assembled the intake and the car started and had a new growl to it - I could hear the secondaries opening now at 3500 - 3700 rpm instead of 4000+ before and the throttle response is/was right on. Well all that was from a trip up and down my road (2 miles). Well I took it to work this morning (approx. 25 miles) and it was running fine up until the last 4 miles and the studder was back with a vengence headbang I have the following code (327) "EGR feedback signal is/was low" - Well before I messed with the t-stat I looked at the egr valve and noticed that some jacka$$ rant routed it directly to the intake bypassing the solonoid (piece mounted to the fire wall) well I routed it correctly but that didn't fix the issue.
Any Help ? This only happens when the car is driven over 25 miles !!!!!
Oh yeah one last point - When I removed the air box to get at the t-stat I noticed someone cut out the entire bottom of the box - but if this was a contributing factor wouldn't it run ****** all the time ?
Scott

Scott

 

[sdpatt]

The EGR feedback signal is sourced from the DPFE (pressure) sensor hanging on the rear driver's side of the intake. If this module is plugged in and the two tubes are connected to the EGR tube, you may need to replace it to correct the situation. If your secondaries are opening before 3,950 rpm and you don't have an LPM, the vacuum required to hold them close is being lost. That would be the job of the electrical servo on the center of the rear intake plenum. It could also be that the vacuum hoses are not routed properly.

From an earlier post:

"The routing of the secondary butterfly vacuum lines is from the center tap on the intake's rear plenum to the front (forward) tap of the black plastic accumulator tank. From the rear tap of the accumulator to the bottom tap of the solenoid. From the top tap on the solenoid to the "T" fitting under the idle air control valve. From the side post of the "T" to the rear bank secondary vacuum diaphragm valve and from the front post on the "T" to the front bank diaphragm valve."

 

[reags8]

Scott
If it is the DPFE (pressure) sensor (I'm assuming thats the small grey box mounted to the back of the intake that has two leads to the egr and yes they are connected correctly) why would this problem only rear its ugly head when the car is run for 25 miles + ?
Also how much is a new sensor ?
Scott
PS I'm not sure if the secondaries are opening earlier or its just that since I cleaned the intake I have that much extra low end ?

 

[sdpatt]

The EGR system is put into play by direction from the EEC and is noy always feeding exhaust gas to the intake. It may only be under the conditions after 25 miles that the EGR is being asked to cycle. The DPFE can be bought through auto parts stores. AutoZone lists the Wells SU243 for $49.99.