Cruising speed hesitation/pulsing
#1
03-07-2005, 07:37 AM
Cruising speed hesitation/pulsing
2000 3.0L 4x4
5-speed
92.5k (original spark plug wires [oops!] and coils, original 02 sensors)
My check engine light kicked on this past weekend and I pulled an EGR code. In my infinite wisdom I forgot the specific code and cleared it. But I dug around and cleaned the EGR valve then proceded to make sure the valve still worked properly applying suction and feeling the valve open and close. Next, I went back to the EGR solenoid and ran the resitance and vacuum tests on it and it seems to work fine. Went back and check for vacuum at the EGR valve again and felt vacuum coming from the solenoid so it seems everything b/t those is working fine.
However, I'm still getting a bit of hesitation or slight pulsing when I am cruising b/t 2,000 and 2,500 rpm. No hesitation when I accelerate or when I completely let of the gas. No rough idling. It's very obvious if I'm in 2nd gear, 2,000 rpm (20 mph) when I'm giving just enough gas to keep it going at this speed. Also seems to be a very slight loss in hp this morning. She usually runs like a dream b/t 45 and 60 degrees and it just didn't have that extra kick I usually get at this temp. Also, the check engine light has not come back on since I reset it. Thanks in advance for any help.
5-speed
92.5k (original spark plug wires [oops!] and coils, original 02 sensors)
My check engine light kicked on this past weekend and I pulled an EGR code. In my infinite wisdom I forgot the specific code and cleared it. But I dug around and cleaned the EGR valve then proceded to make sure the valve still worked properly applying suction and feeling the valve open and close. Next, I went back to the EGR solenoid and ran the resitance and vacuum tests on it and it seems to work fine. Went back and check for vacuum at the EGR valve again and felt vacuum coming from the solenoid so it seems everything b/t those is working fine.
However, I'm still getting a bit of hesitation or slight pulsing when I am cruising b/t 2,000 and 2,500 rpm. No hesitation when I accelerate or when I completely let of the gas. No rough idling. It's very obvious if I'm in 2nd gear, 2,000 rpm (20 mph) when I'm giving just enough gas to keep it going at this speed. Also seems to be a very slight loss in hp this morning. She usually runs like a dream b/t 45 and 60 degrees and it just didn't have that extra kick I usually get at this temp. Also, the check engine light has not come back on since I reset it. Thanks in advance for any help.
#2
03-07-2005, 05:13 PM
Maybe some more information would help ...
The check engine light kicked on again today and I pulled DTC P0401 (EGR Flow Insufficient). The solenoid seems to be open if you take it off and blow through it. EGR valve opens when vaccuum is applied, the vaccuum line b/t the solenoid and the EGR valve is clear. I've performed the voltage tests that the Haynes Manual suggested and am at a complete loss. The problems I've mentioned above only happen at normal operating temps. Only thing I can think of would be clog in the pipe between the valve and the manifold. I'm ready to grab at straws if you have any suggestions. Thanks!
The check engine light kicked on again today and I pulled DTC P0401 (EGR Flow Insufficient). The solenoid seems to be open if you take it off and blow through it. EGR valve opens when vaccuum is applied, the vaccuum line b/t the solenoid and the EGR valve is clear. I've performed the voltage tests that the Haynes Manual suggested and am at a complete loss. The problems I've mentioned above only happen at normal operating temps. Only thing I can think of would be clog in the pipe between the valve and the manifold. I'm ready to grab at straws if you have any suggestions. Thanks!
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