Hesitation / Jerking : 2000 Cavalier 2.2

[TheTrader]

Hi Everyone, well, we are having another issue with my girlfriends Cavalier.... the same thing happened last year, and we tried a few different things but I forget when the problem finally stopped... I know it happened the same time of year... ??

Anyway, I have been thinking, and I think replacing the fuel filter was the last repair I did before it stopped... is there any chance the fuel filter could need changing again??? I am used to older VW's where you can run a fuel filter for like 15 years and never change it.... anyway....

The problem happens mostly on highway at constant RPM / speed, and it like a little jerk / hesitation... it can get pretty bad and annoying on the highway, and it happens around town too....

I just put new plugs in last year (one of the repairs, dealer plugs) and I just now put new Bosch Premium wires on it......

do I need to do the fuel filter again????

-Daniel

[sunrunner_pei]

According to the mechanics here, fuel filters should be changed annually. I do mine every 2 years. It's probably the least expensive thing to try, aside from fuel injector cleaner, so I'd probably do that first. :)

[TheTrader]

Originally posted by sunrunner_pei
According to the mechanics here, fuel filters should be changed annually. I do mine every 2 years. It's probably the least expensive thing to try, aside from fuel injector cleaner, so I'd probably do that first. :)

wow... you are fast... I just PM'd you to ask you to read this :)


We have an injector cleaner to throw in before we hit the highway on friday.... I like to put that stuff in before I fill-up & a trip.... so hopefully by the time we get to Perth Andover it should be driving fine :)

I think it needed the wires, since I misted water over the old ones the other night and could see a few places where it was arcing down near the plug and along the wire

Just now when I did the wires, I also checked the gaps on the plugs :)

[sunrunner_pei]

I was going to suggest plug gap next. :lol:

[TheTrader]

Originally posted by sunrunner_pei
I was going to suggest plug gap next. :lol:

I am going to try the injector cleaner and a nice full tank of gas before we hit the highway friday and cross our fingers.... we dont have the cash to be blowing on repairs right now!!

[99GrandAMSE]

... replace the wires if they are in question, check the plugs and replace, if necessary ... air filter, maybe ... check all the standard maintenance items ... for fun, try a little high grade gasoline or octane booster and see if it changes ... another thought, throw a little gas line de-icer in the tank to see if it gets better as it will take care of any water that you might have ... have you noticed whether or not it does it at specific fuel levels? ... fuel filter would be a good idea as already mentioned, just in case

[rixGAphx]

2000, 7-yrs old, so about 80k miles?
What tranny, auto or manual?
I *assume* the SES icon isn't 'on', or you would have said so, right?

Symptom:
"...The problem happens mostly on highway at constant RPM / speed, and it's like a little jerk / hesitation.
It can get pretty bad and annoying on the highway, and it happens around town, too...."

Well, that is NOT a symptom of a clogged fuel filter.
Fuel filters for the GA (and I *assume*) for the Cav, last a good 30k miles of 'normal' conditions.
* Unless you have air that's even dirtier/dustier than Phoenix (and I assure you, you don't :roll: ); or,
* You occasionally purchase off-brand gas or are forced to use some halfway-past-nowhere mom-n-pop convenience store.

When the fuel filter is really clogged:
* It will flow an adequate amount of fuel for idle and for cruising.
* But when you need more gas-per-second while flooring it or running at 75+ mph, then the car will stumble from low fuel pressure/inadequate fuel flow.
* * *

If this IS an engine problem (which I don't think it is), then it is related to either the vacuum system or fuel-pressure/volume related, since neither of these is monitored by the PCM.
The PCM throws a code and SES icon for nearly every other possible engine operation.

* Vac problems are almost always more noticable at idle/low-rpm than when at cruising or higher rpms.
They don't go away, but the increased engine speed kinda 'masks' them.
Vac problems *usually* cause other problems with the HVAC controls, Cruise Control, and/or power brakes; since you haven't mentioned these, will eliminate 'vacuum' as a problem for now.

* Fuel pressure/volume:
The fuel pump is working well, and we've determined that the filter prolly isn't at fault.
The timing and duration of the fuel injection doesn't have any OTHER symptoms that are auaully associated with it or the injectors themselves, so these seem OK; I wouldn't look there for the problem.
The Fuel Pressure Regulator *may* be going bad, and it isn't 'monitored' so doesn't throw a code if it's bad. About $50; sorry, I don't know of any tests for it.
* * *

The symptom seems to point straight to a Torque Converter Clutch problem with GM automatic trannies.
If the car has an auto, this is where I would start looking.
One way in which this thing 'fails' feels like a hic-cup or 'stumble' of the throttle, but has nothing to do with the engine.

Minor problems with with the TCC throw a code about half the time IMO, so the fact you don't have a code doesn't mean the problem isn't there.

The TCC locks the TC (stops the internals of the TC from spinning) for better gas milage, then unlocks for better performance.
It's electric (there's a solenoid in the tranny that operates the clutch) and is controlled by the PCM.
Especially while accelerating slowly or climbing a moderate grade, the tranny 'hunts' back-and-forth for the best combination of milage and power-to-the-wheels. This is normal, but annoying.

If the wires to the tranny are frayed, or the connectors aren't in good shape, then the 'lock-up' may lock-unlock on its own, without signal from the PCM.

On the top of the tranny, a few inches behind the engine, is a large electrical connector with several wires.
Clean the area around the connector thoroughly, then unplug-replug the connector several times.
This simple unplug/replug will usually clean minor dirt and crud from the connector pins and sockets.
Also check the wires here for kinks or damage; I *think* there's a black 1/4" vacuum tube going to a nipple in this same area of the tranny, so inspect it for damage.
* * *

Every good brand of gasoline has the proper concentration of Fuel Injector cleaner in every gallon, to keep your engines free of fuel system deposits.
It's all the same as Chevron's "techroline", and it's the same stuff that's sold in bottles.
It's a pretty powerful cleaner.

If your FI system shows signs of dirty injectors, a bottle of stuff thru the tank is a wise first step.
At the 15,000 minor service, another bottle is a prudent step especially if you had to buy a bunch of mom-n-pop stuff the prior year or so.

But a bottle every fill-up before a trip could get pretty expensive, and not really do ANYTHING (since your injectors are already being cleaned by the good gas you buy).
* * *

Water is much heavier than gasoline, and flows straight to the bottom of the tank.
An appreciable amount of water can stop an engine from running, until the fuel pump finally sucks-up some gasoline and the injectors squirt it into the manifold.

If you usually drive with a low-level of fuel in the tank, and only put-in a few gallons at a time, then there will be moist air in the top of the tank.
This moisture can condense on the metal walls of the tank.
Each drop would flow quickly to the bottom, and be picked-up immediately.
A single drop or two of water of injected water, instead of gasoline, would casue the engine to stumble, then continue fine for a while 'til the next drop was injected.
Filling the tank forces-out all moisture-containing 'air'.
The tank is a sealed part of the vapor recovery system on modern cars.
So as the tank level drops, the 'air' that goes into it is heavy with gas vapor (from the charcoal canister at the engine) and has very little moisture in it.

The above scenario requires: cold climate, moist atmosphere, and maintaining a low-level by frequent 'filling' with only a few gallons.
Never happens here in Phoenix, but sounds like the perfect weather description of Moncton.
It's a possibility, but pretty rarely encountered.

I hope all (or some :D ) of this helps.
Have a great trip to Perth-Andover,
-Rick

[TheTrader]

I am leaning towards the water in tank suggestion rick.... the car is usually running very low on fuel.... we only drive back and forth to town (about 5km each way) and it could be sitting around for over a week with less then a quarter tank...... I was also thinking that because it runs low alot, that the fuel filter may be excessively dirty?? does that make sence....??

We had the trans serviced last year... new filter & fluid.... so hopefully its not internal... I noticed that big plug on top of the trans last night and give it a good dose of WD-40.... will try cleaning it off tonight :)

thanks guys

[sunrunner_pei]

From what I'm told, the quality of the fuel here in the Maritimes isn't up to par with the rest of the nation. Could be total BS, I don't know. But that was the reasoning behind the need to change the fuel filter more often.

[99GrandAMSE]

Originally posted by rixGAphx
... Never happens here in Phoenix, but sounds like the perfect weather description of Moncton. It's a possibility, but pretty rarely encountered ...

Actually Rick, it does happen a bunch up here which is why I suggested the gas line antifreeze being it, in simplistic terms, connects to the water and allows the car to pass/burn it ... we have a strange climate here which does even stranger things with moisture so your explanation was a much more thorough version of what I was getting at :lol: ... thanks bud!

[TheTrader]

Originally posted by 99grandamse
Actually Rick, it does happen a bunch up here which is why I suggested the gas line antifreeze being it, in simplistic terms, connects to the water and allows the car to pass/burn it ... we have a strange climate here which does even stranger things with moisture so your explanation was a much more thorough version of what I was getting at :lol: ... thanks bud!


This morning I put a full tank of gas and a bottle of injector cleaner in it (had some of it, didnt have any antifreeze) so, we shall see how it preforms now.... might throw in some antifreeze too :)

[99GrandAMSE]

... it is the antifreeze that will get rid of the water ... you should pick up a bottle, just to see how it works :)

[TheTrader]

Originally posted by 99grandamse
... it is the antifreeze that will get rid of the water ... you should pick up a bottle, just to see how it works :)

I will have to... because its still doing it !! bugger....

[99GrandAMSE]

:(

[TheTrader]

Originally posted by 99grandamse
:(

I know... and I REALLY dont want to have to take it to a trans shop to get it checked.... you walk in the door of any place like that and they pretty well charge you 50 bucks

[99GrandAMSE]

... I just have a GUT feeling it isn't the tranny but of course, it is only a feeling ... honestly Dan-o, if you drive with a very low fuel tank often, you could have water and/or a slightly more restrictive fuel filter due to dirt build up :(

[freekLED]

All good advice, especially Ricks suggestion about the TCC & the electrical plug on the trans. If the antifreeze doesn't fix it check your wiring to the tranny.

My 96 Cavy used to do the same thing, but only when I drove it short distances (<10 km) & mostly in town. I found out water had entered the wiring harness to the trans and corroded 1 wire (I forget which), spliced it & all was good after that. How the water got in the harness and through the wire covering/insulation I have absolutely NO idea, it was all OEM and hadn't been touched since I got the car (new). I have had several corroded wire issues (headlight harness, turn signal) with the Cavy, but none with he GA...yet.

Hope it's an easy fix in the end.

[TheTrader]

Well, I the antifreeze might have made a difference... it was really doing it alot tonight, drove to wally-world to buy some, and pulling into the parking lot it started doing it pretty bad... but when we stopped I just dropped it in neutral and held it at like 2500 RPM and the engine was runnin like crap.... so that re-assured me it shouldnt be tranny related....

so, we put the antifreeze stuff in and drove around more, and it still did it, not near as bad... and seemed to be doing it less at highway speeds then at lower speeds... did it once or twice in the ride home...

anyway, with 1 bottle of injector cleaner & 1 bottle of antifreeze in the full tank of gas, all the stuff besides the gasoline in there, it might not run perfect untill its all burned out anyway...

hopefully it will work itself out....**crossing fingers**

I am going to take a look at those connectors tomorrow after work... its getting dark out now

[99GrandAMSE]

Good news so far brother :)

[99GrandAMSE]

Per an earlier conversation with Dan, is this what you wanted?

[TheTrader]

actually thats for the fuel injectors, is there anything about testing the ignition coils? the things the spark plug wires plug in to... and it looks like thats for a 2002, which I think had the Eco in it, this is a 2000 with the old 2200 motor :)

My brother mentioned something like using a voltmeter to test the resistance of the coils??

Thanks bud, your a huge help!!!


PS: Bought an OBD2 Code Reader tonight.... "No Codes" ... bastard car not throwing any codes!!

[99GrandAMSE]

Ignition!!! DAMN ... sorry, I thought you wanted the fuel injectors ... my bad :lol:

[99GrandAMSE]

Found a couple Bulletins describing SOMETHING like your situation ...

#1

[99GrandAMSE]

#2

[TheTrader]

the first one sounds kinda like it... accept it allways starts perfect.... but the starting is an "and / or" thing..... the second one was for the 2.4 LD9 motor :)

Anything on testing the coils turn up in there yet?

Might see if I can get a quote on that fuel strainer thing, only thing that sucks is it sounds like I might have to drop the tank... unless the sending unit is on the side....?

[99GrandAMSE]

Originally posted by TheTrader
the first one sounds kinda like it... accept it allways starts perfect.... but the starting is an "and / or" thing..... the second one was for the 2.4 LD9 motor :) ...

Well shit, didn't notice the 2.4 on the second one ... again, my bad :lol:

Originally posted by TheTrader
... Anything on testing the coils turn up in there yet? ...

Not sure why I can;t find anything on it but I'm still looking.

Originally posted by TheTrader
... Might see if I can get a quote on that fuel strainer thing, only thing that sucks is it sounds like I might have to drop the tank... unless the sending unit is on the side....?

... I suspect it is in the tank :(

[TheTrader]

Originally posted by 99grandamse

... I suspect it is in the tank :(

hmmmmm I wonder if the landlords will mind me jacking up the car and pulling the gas tank in the parking lot??? :D

[SE2000]

Have you though about a road trip?

Plan on driving the car back and forth over the highway, don't go too far from home just in case and work the cleaner through the tank. Go through what you have and fill up. the cold and water in the car will clear out after an extended trip.

[TheTrader]

Originally posted by SE2000
Have you though about a road trip?

Plan on driving the car back and forth over the highway, don't go too far from home just in case and work the cleaner through the tank. Go through what you have and fill up. the cold and water in the car will clear out after an extended trip.

I was thining about that actually...... this weekend we had a good 3.5 hours drive to do and I didnt feel comfortable taking it on a trip like that, so we took the GA.... sometime this week I think I will take it for at least an hour drive somewhere!

[TheTrader]

Looks like it might be working itself out.... took it for a rip up the highway, just for a few minutes though, but I wound it right out, and by the time we were driving home it seemed to be running pretty good... so cross your fingers for me!

[99GrandAMSE]

... maybe it is working through the 'old' gas or the injectors are cleaning themselves :shrug:

[Spoiled]

I had a hesitation problem with my ole Cavalier. I would add a bottle of gasline antifreeze/water remover to each full fill up and the problem went away after going through about 2 full tanks of gas. I had been to a different older gas station when I first noticed the hesitation, so don't know if that was the cause of the hesitation, maybe water in their old tanks or what it was. I never visited that gas station again, kept with my regular spot and never experienced the problem again.

My Grand Am, well, during cooler/colder weather, it'll hesitate until it warms up. So, I let it sit for a couple minutes to warm up before I leave, no problems after that.