: egr blockoff



stoveguyy
10-30-11, 10:27 PM
96 sts. my egr likes to stick if i drive hard. i have removed it and tried to clean the shaft with solvent but it does not seem to work. i know a new one is $125. if i unplug egr, i am sure i will get a code. could i take off egr and make a simple block off plate and reinstall?

dkozloski
10-31-11, 01:33 AM
96 sts. my egr likes to stick if i drive hard. i have removed it and tried to clean the shaft with solvent but it does not seem to work. i know a new one is $125. if i unplug egr, i am sure i will get a code. could i take off egr and make a simple block off plate and reinstall?

Per GMPowerTrain engineers; your gas milage will go in the toilet.

Submariner409
10-31-11, 11:20 AM
Also, EGR directly affects part-throttle fuel mixture and ignition control. Disconnect it or plug the passages and the engine will knock and rattle like BB's in a tin can. Guaranteed.

Try it - disconnect the electrical connector and drive the car. You can clear the resulting codes later - but the engine will knock and sound like crap after it goes open loop and the emissions systems begin to operate.

stoveguyy
10-31-11, 10:50 PM
the egr valve is a solenoid. so its fully open or closed? not modulating or partially open? in normal driving the egr is opening/closing constantly? i can go weeks with no issues. than i punch it and 99% of the time the egr will stick and car will usually die if i try to idle.

ternstes
11-01-11, 05:28 AM
Would you like to try a used one off of a 1999 STS?

Ranger
11-01-11, 12:38 PM
the egr valve is a solenoid. so its fully open or closed? not modulating or partially open? in normal driving the egr is opening/closing constantly? i can go weeks with no issues. than i punch it and 99% of the time the egr will stick and car will usually die if i try to idle.
No. The EGR valve on the Northstar is a linear EGR. Much like the TPS or the ISC motor it is pulsed and the pintle position is variable depending on conditions and may be anywhere between wide open or closed.

"A Linear Exhaust Gas Recirculation Valve. In most EGR designs, the flow is "Open Loop," in which the system has no feedback mechanism to monitor actual flow and then to correct it. The linear EGR valve is unique in that the control module continuously monitors pintle height and continuously corrects it in order to obtain accurate flow, making linear EGR a "Closed Loop" system.

When the solenoid is de-energized (control module breaks the circuit), the pintle is sealed against the orifice, blocking exhaust flow to the intake manifold. The height of the pintle is read by the pintle position sensor, and the control module closes the loop on desired position versus actual position read, changing the pulse width modulated command to the solenoid accordingly, until the actual pintle position equals the desired pintle position."

If you EGR valve is sticking, pull it and clean the pintle valve til it moves freely and does not stick in any position. A dentists pick is a great tool for this. You can find them at dollar stores for a buck each.

stoveguyy
11-01-11, 03:36 PM
I got a used one. Same yr car. Fuel rail was gone on boneyard car. I hope used part works better. Drove to yard with caddy. Runs fine if you tiptoe. Hard to not punch it to get around slow cars.