2000 4.2 V6 Surging @ Idle
05-26-2008, 01:10 AM
#1
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2000 4.2 V6 Surging @ Idle
2000 4.2 v6, RPM will surge from idle to about 1400 rpm. this seems to happen when engine is at operating temp. Truck will try and jump forward at stop lights. I have checked the PVC and for vac leaks. Any one have any clue what I should be looking for.
07-09-2012, 10:14 AM
#3
Junior Member
Surging idle
You are not alone here. I cleaned the IAC and performed the infamous SeaFoam treatment on my 97.
My truck, on the other hand, idles at 1000 RPM. As it warms up to temp, it will then surge down to 700 and back to 1000, and keeps a steady rythm at it. Before the treatment, It would run smooth under a light load. Such as if I turned on the AC. But now it does it all the time unless you keep the idle up above 1000 rpm.
Also, it has a bad hesitation and wants to choke out when giving it gas, breaking up and then catching up to running smooth again...
My truck, on the other hand, idles at 1000 RPM. As it warms up to temp, it will then surge down to 700 and back to 1000, and keeps a steady rythm at it. Before the treatment, It would run smooth under a light load. Such as if I turned on the AC. But now it does it all the time unless you keep the idle up above 1000 rpm.
Also, it has a bad hesitation and wants to choke out when giving it gas, breaking up and then catching up to running smooth again...
07-10-2012, 09:58 AM
#4
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May want to clean the MAF sensor to be on the safe side. My 4.2L had an extremely high idle when I slowed down at stop lights (would last for about 4 secs and return to normal). After cleaning the MAF, it went away.
Like others have said, also check for vacuum leaks. The 4.2L is notorious for developing leaks in the hoses located at the rear of the upper intake manifold (passenger side) near the firewall. Good luck!
Like others have said, also check for vacuum leaks. The 4.2L is notorious for developing leaks in the hoses located at the rear of the upper intake manifold (passenger side) near the firewall. Good luck!
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2001 f150 4.2 2024 (01-14-2024)
01-14-2024, 01:27 AM
#6
2001 F150 v6 4.2 Rpm surges when put into drive or reverse from park
Has anybody found anything about this? My 01 4.2 does this constantly and had been since i got the truck in 2020. It gets better when some pieces are changed but then ends up like it was from the start. No valves in the back of the engine are cracked the were all replaced and egr sensor is brand new along with most of the other sensors related to anything like this. It only does this in drive or reverse from park. Not in neutral. It starts at 1000 rpm then shift into reverse and it drops to 500 then up to 900 then down to 300 then back up and so on. **** is getting very old. Please help
