Thread: Hesitation at 2000 RPMs

I've been getting a little hesitation and RPM bouncing at around 2000 RPMs when in the higher gears. Plugs have recently been changed, no codes thrown. Any ideas what it could be? Bad MAF maybe? I've replaced it once with a junk yard one, so it's possible. Thoughts?

have you checked the intake to make sure that its not clogged?

I'll take a look. I cleaned the K&N oil back in March, and it only started happening about a month ago. But it's possible.

Yep, me too. I guess we both just have sh*tty cars.

I am in the same boat. My '01 GT will surge and hesitate when the RPMs are close to 2k when cruising at part throttle. Letting off the gas or pushing it further to downshift causes the surging to cease. The tach bounces in sync with the surge.

Anybody figured out and fixed this condition?

Hmm, My cat and wires were swapped about 80,000 miles ago, the plugs about 25,000 miles, and the MAF Sensor 40 thousand. Could be O2 or ECM, but since it's really only an annoyance for me and I intend to either give it to a friend's son or drive it until 200,000 before I try to sell it. Just hope if I do sell it, it doesn't happen during the test drive. Haha.

I would try ICM.

I have a new o2 sensor and my car does this. I am going to try plug gap and if that doesn't help, I'm replacing my ICM.

I've also replaced my Plugs, wires, coils, checked for vac leaks, and I still have no solution yet.

i have the same issue. i found this on automotive forums

[COLOR=blue !important][COLOR=blue !important]Engine[/COLOR][/COLOR] Controls - Intermittent Chuggle/No DTC's Set

Bulletin No.: 05-06-04-058

Date: September 07, 2005

TECHNICAL
Subject:
Intermittent Chuggle or Fishbite on Light Acceleration or at Highway Speeds with No Diagnostic Trouble Codes (DTCs) (Replace [COLOR=blue !important][COLOR=blue !important]Throttle [COLOR=blue !important]Position[/COLOR][/COLOR][/COLOR] (TPS) Sensor)

Models:
1995-1999 Buick Riviera
1995-2004 Buick Regal
1995-2005 Buick LeSabre, Park Avenue
1997-2005 Buick Century
1995-2001 Chevrolet Lumina
1995-2002 Chevrolet Camaro
1995-2005 Chevrolet Monte Carlo
2000-2005 Chevrolet Impala
1995-1997 Oldsmobile Cutlass Supreme, Ninety Eight
1995-1999 Oldsmobile Eighty Eight
1998-2002 Oldsmobile Intrigue
1995-2002 Pontiac Firebird
1995-2003 Pontiac Grand Prix
1995-2005 Pontiac Bonneville

with 3800 [COLOR=blue !important][COLOR=blue !important]V6 [COLOR=blue !important]Engine[/COLOR][/COLOR][/COLOR] (VIN K - RPO L36)

Condition

Some customers may comment on an intermittent chuggle or fishbite on light acceleration or at steady-state [COLOR=blue !important][COLOR=blue !important]highway [COLOR=blue !important]speeds[/COLOR][/COLOR][/COLOR] (typically 80-105 km/h [50-65 mph]) with no PCM DTCs set. This condition may lead the technician to suspect the TCC circuit or torque converter.

Cause

This condition may be caused by intermittent operation of the Throttle Position (TPS) Sensor.

Correction

In observed cases, the Tech 2(R) is not fast enough to consistently detect this condition during a snapshot. It is recommended to use a DVOM set to the min/max recording mode. Connect the DVOM at the TPS connector (positive lead to TPS feedback signal pin and negative lead to TPS ground pin). Duplicate this condition by driving the vehicle. If the voltage dropout (less than 0.45 v) is recorded on the DVOM, replace the TPS sensor and re-evaluate the vehicle before continuing with other driveability or transmission diagnosis.

im gonna get a new tps and see how that goes. those links lead to the original thread. idk why there all over the page

Don't for the coversheet on the tps report.

RockAuto shows it's the same part as what's in my Impala, so I can try a switcharoo and see if it fixes my problem. If it does, the IMP gets a new TPS!

OK, where on the throttle body is the TPS? I know what the MAF sensor is, but there are two other electronic items on the towards the front that look similar but have different colored gaskets - one blue, one purple. My Haynes manual shows a picture that looks nothing like my TB. I want to try first taking the TPS off my Impala before I go buy a replacement. I know I could buy the replacement then match it up, but if I have to open the part up, the store may not take the return. Anyone swap it remember which one? It's the 3800 engine.

Alright, I took the TPS from my Impala and placed it on my Grand Prix. I had NO SES light on the Grand Prix before I did this. I put the Impala TPS on the GP, and disconnected the negative battery connection to clear any codes. After my second restart, SES light was triggerred, P0122 - Bad TPS code. I have not had the same hesitation problems in my Impala, and of course there has never been a SES light on the Impala.

So my original plan of moving Impala TPS to Grand Prix is a no go. I evidently have two bad TPSes! But since there has been no trouble on the Impala , I'm going to put its TPS back in place, and buy a new one just for the Grand Prix.

It's entirely possible that the Impala TPS has been bad for a while, but at highway cruising speeds, I'm under 2000 RPM, and when I do punch it, the supercharger may cover any hesitation I may have. I'll have to buy a new TPS for the Impala eventually, but I want to minimize the wallet impact.

Good news! I took a look at the code that's not triggering the SES light on my GP, and saw it was marked "pending." So the TPS was bad, but not BAD bad. Anyway, picked a new TPS up from Advance Auto and installed it. Checked for codes, all cleared; I did not have to clear them. Woohoo!

I know, Rock Auto is probably cheaper. I found a coupon code for Advance, and it placed the TPS well below Rock Auto. Plus, I was able to pick it up within an hour of ordering it. I went with the BWD brand, which I know isn't top of the line. But it's installed, no codes, and my drive into work tomorrow should confirm/deny if that was the problem.

okk, are you still experiencing the hesitation or did it solve the issue?

I haven't had a chance to take the car out yet for a test drive, and might not get the chance until tomorrow evening. But I will report on what does happen. I considered taking my tools to Advance, as the drive home would have given me time to test it out. But I didn't have the time at the store.