Engine jerking and hesitation

[BoogerBrain]

Hello,

I have a '97 2.4L 5 Speed that I have been having some problems with for a while. I was wondering if anyone else had experienced the same thing and if so, what they found it to be. Here goes:

When I get into a low RPM range, the car will jerk like fuel is being cut out. Imagine being in a car with someone who is learning to drive a standard and dumps the clutch without enough gas... That's sort of what is happening with the car.

I had it tuned, and replaced all filters but the problem has persisted. The car only has 90,000 KM (less than 60,000 miles) and I change the oil every 5000K. I don't beat on the car or anything.

Does anyone have any idea what might be causing this? Is it related to the fuel system, exhaust system or otherwise perhaps? Maybe another way to describe it is to say it feels like the car is being choked of power somehow.

Any suggestions would be greatly appreciated.

Stephen

[DontPassTheFence]

that wa hhappening to me as well, but not as drastically. i replaced the fuel filter, but its such a damn pain in the ass to do.

offtopic :: do you have any pics/ how to's on hacking your shifter and putting a knob meant for an import on there?? i got a ractive shift knob i think, or some company, but anyways its too small, so i was just wondering if you had some tips/etc for anyone wanting to hack saw the shifter and mod it, and make it work and look good.

[urweak]

try replacing your ignition module and coil packs. You can most likly find a used pair on ebay for about 40 bucks or so. See if that helps.

[thegeswho3]

i have that problem when i first start my car,(and mine is exactly the same as yours by the way 97 gt 5sp). Mine stops after about 2 min of driving tho. Ive just figured that its taking the old girl a few minutes to get the gas flowing good.

I had a probe before my GA and my mass air flow sensor went bad and i got very similar jerkiness and a feeling of the power being choked off. I would assume air flow ssytem before the fule, but im no mechanic.

No check engine light???

[carlover626]

Sorry I don't have an answer, although I do have the same problem!
Same Engine/Trans, but my problem is more when I start it cold or after it has sat for a couple of hours. It starts fine everytime, but if I push the gas at all after I start it and let it idle again the RPM's go from 900 to like 2000 for like 10 seconds and back down to normal. If I am trying to move right after I start it, it acts like it isn't getting any gas and jerks forward a few seconds later? I am going to do the plugs and maybe the boots this weekend, what else could it be?
More spurattically when I am in traffic, sitting in neutral, my RPM's will drop down to like 500 for a quick second and go right back to about 900 and drive like nothing happened? Could these be related?
Where is the Mass Aif Flow Sensor you talked about? And also the TPS? I'm guessing it could be either of those also?

[urweak]

I have this problem too, i know a guy that replaced his ECM and it fixed the problem. I know my ECM is not working right and needs replaced.

[carlover626]

Is this something I can fix myself? I don't have my Haynes manual with me so I'll look that over this weekend. Is it expensive? Can you tell me where it is? Thanks a lot, that is the first I have heard of that.

[urweak]

I would first try replacing the parts i mentioned first, if that doesnt work maybe replacing the ECM will work.

But the ECM is going to run you 100-200 dollars from an auto store, new from a dealer list is over 300, then you have to pay about 100 to flash the computer, and most licky when they flash it they will charge to install it too. About an hour or two worth of work.

[BoogerBrain]

I hadn't had it checked for codes, but it wasn't throwing a CEL, so... So far I have received 3 different recommendations and they are:

Ignition module and coil packs
Mass air flow sensor
Get the exhaust tested
Replace the ECM

Now, I'm no mechanic by any stretch so I appreciate the suggestions everyone... In all honesty, I was thinking that it had something to do with the exhaust, the symptoms described are exactly what the car is doing.

I will keep everyone posted with my findings.

Thanks again for all the suggestions.

Steve

Oh and in regards to the question about the shifter, what I did wasn't fancy.

I cut the shifter stick (sorry, don't know the techincal term) with a hacksaw and then cut a cross hatch patern into the top of the stick (think letter 'x'). That allowed my to squeeze the stick small enough to get the momo shifter on with a rubber mallet.

I can't say that I'd recommend this route to others; I don't think I could ever get that knob off if I wanted to, it is on there TIGHT. But for my purposes it worked out well and looks neat and has been that way for many years. There's probably someone on here with a better suggestion though.

[DontPassTheFence]

hmm... i think I may do this, since the new shifter i have is metal, it would never wear/etc -- i think id want it on there permanently... and im not gonna sell this car, im going to have it until either I die or it dies... which comes first. I like the idea, i will bust out the hack saw tonight and see what I can do. thanks for the suggestion

[bobgagt]

My sunfire does the same thing. Its not ECU, its not plugs or ignition module. I'm told by people on the jbody forum that its the coolant temp sensor that goes into the head. I bought the new sensor for $9 now, but I haven't gotten around to do it yet. I have the hesitation after I have it running for a minute.... sputter sputter.... give it a rev, its fine. Anyways I'm TOLD its the computer not quite seeing the right resistance (temperature) from the sensor at a certain temp and then makes the car run rich which floods it out for a bit then sputter sputter.

Well whatever, this is what I'm told... I'll let you all know if it works fine when I change the sensor.

-Bob

[carlover626]

That's not the first time I've heard the Temp Sensor being the culprit. Let us know how it worked out.

[bobgagt]

I still have to get around to changing it.

[Lash]

The colant temp sensor problem is ONLY when the car is first started (cold start) and will only last a few minutes. If the problem is occuring longer than that you have another problem.


#2...you don't have a MAF (mass airflow sonsor)....so throw that idea out the window.


When was the last time that you checked your plugs?


At what RPM does the engine seem to 'clear out'?

[carlover626]

I have recently changed out my plugs at about 85,000 miles. My problem happens at cold start and after it has sat and cooled off a bit on the guage, otherwise it is fine (no startup problems).
About the RPM question, mine will idle normal at 1200-1500 (Cold) then drop down to like 500 and kick back up a couple of times to like 1500 and back to "normal" (1000-1200 depending on how cold the engine is), it has died on me as well.
This all happens within about 10 seconds, and if I try to give it gas it will do nothing to the RPM's.
Thanks all!

[956jesse]

my 2001 Grandam motor 2.4 does the same thing when i try to start the car in the morning it die or jerk like fuel is being cut out...take the car to Autozone ..for the computer check up..it show the O2 sensor .

[a-brat]

I get all the same problems when the car is still cold.
I am no expert. When this hapens I tried steping on the gas a little - nothing - zilch - it does not rev- like I'm not giving any gas at all. then slowly it starts to pick up again, and runs normal.

[carlover626]

My problem was a little more drastic a day ago when it sat all day and I started it that night to go out. It did the same thing but it was a lot more prolonged and it seamed like it was searching for the right RPM's.
I'm no expert either, sure wish sometimes that I was!
OK, so something I can check are O2 sensor, Coolant temp Sensor, and Spark Plugs. I am down to the two sensors.
Any other ideas?

[IamChevyman5]

see my post under "know any ways to improve an engine? make it better while still keeping it stock?" Because that sounds a lot like what my car was doing.
It was the EGR valve if you don't look at it.
later
Dan

[carlover626]

Thanks Chevy Man, I'll have to look around this weekend for the EGR valve and a gasket.
I have this and my moms car to fix, her 86 Celica is sputtering at low RPM's and I am thinking it is the fuel filter since she has had the car for years and it has never been changed to her knowledge at 227,000 miles!

[IamChevyman5]

that's exactly what mine was doing as well, a combination of the two of your's, and your moms...mine would sometimes stall out in the low RPM's though. Go to an auto parts store, ask if they have a gasket for you, they'll probably say no, and then ask them to check the nearby stores on their computer for you. That's what I did, and I got it second store, and the car was fixed in about half an hour, and the check engine light turned off the next day, making me very very happy... Very big looking problem solved by a $2.50 gasket and a 10 minutes getting carbon off.
Dan

[carlover626]

Okay, here is an easy one for you, what do I need to do to get to the EGR Valve/Gasket? I have not taken the Throttle Body off of my car and to be totally honest I don't know how? :(

[IamChevyman5]

You know the black plastic piece on your 2.4 right in front of the silver metal piece with "2.4 twin cam" on it? There's a few screws on that, take those off, and take the visible hose off to the right. There is a hole in the middle of the black plastic thing that GM made for you...it's not for nothin, it's so you can take another clamp off that's on the inside of the plastic. There's also a small hose in the back that's connected to it. Take all that off, then take off the plastic thing (it's much easier than it sounds) and there will be your EGR valve in the high right upper corner of where the black plastic cover was. Take off the electric looking thing, I think it had a blue top on mine. And you'll take I think two screws off and you'll have the valve off.
Congrats.
Dan

[PeteXcore]

i didn't see anyone with mine, so here it goes. I have a 2001 2.4L automatic, and i usually let it run for 30 sec. or so in the morning while i take the sun blockers out of the winshield, and either when i put it in reverse, or into drive from reverse to drive away, i kinda hesitates for a second, but once it gets going, it's fine. it's not a big deal, but i dont want it to turn into a big deal. ideas?

[carlover626]

Coolant temp sensor and the EGR valve are others it looks like you have not done (neither have I). I am at a loss myself, and I am not going to be replacing things just to find out it isn't it.
Anyone know anything new?

[Bpow]

I've had this problem since day one 4 years ago.....replaced many things and I believe I have finally traced it back to the TCC inside the tranny....GM started making the piston out of aluminum inside the tcc to reduce vehicle weight leading to the cylinder wearing down and allowing fluid to bypass the piston when it shouldn't making the car surge forward....I am trying to find some way to hook in a switch or bypass the tcc when it runs bad instead of replacing the damn thing. Just something for you guys to go off of.

[carlover626]

Well thanks I wish (Oh wait no I don't) that I had an automatic, but I have a 5 Spd. and there isn't a TCC.
Damn, this problem looks as if it is there and won't go away EVER for a lot of people.
Maybe we can complain to GM :) ?

[JustinBTE]

I am having the same problem with my '99 grand am 2.4 but its a constant sputter all the time when im idling no matter what the temperature is. Auto Zone told me a few things. Oxygen sensor is defective, bad plugs/wires/coils, a vaccum leak, injector fault, and high or low fuel pressure. im trying to figure out right now as i type this which one of these could be the problem.

[carlover626]

Do you have any problems accelerating? Do you have an engine light? If so, Autozone can check the codes for free.
You don't have plug wires, but depending on your milage you could need plugs. Just get the stock AC Delco Platinum's (about $30 for all 4), others can cause problems. As far as the 02 sensor and injector faults, if you don't have a Check engine light I would look elsewhere.
Do you keep up on the regular maint? (Air filter, Oil, etc?)

[JustinBTE]

this problem started for me almost a year ago. My accerlation was horrible, it just wouldnt go at all but i changed the plugs and the whole problem went away for a few months. Now its back except the accerlation is still normal and it only sputters when its idling or when its below 2K rpms. my check engine light came on yesterday and all those things i mentioned are what autozone said could be wrong with it. those are the codes that set off. Yeah i keep up on everything. every now and then i put in some Fuel injector fluid. I'm thinking about changing the Fuel Filter and/or the O2 sensor.

[carlover626]

Do the fuel filter before the oxygen sensor, it's cheaper and most of the time the 02 sensor will throw a check engine light.
If you have never done the FF, I am going to bet that is the culprit.
Look around for instructions on the fuel filter, these can be a PITA and since it is not protected from rain, sand, and road grime, the damn connections can be nothing but trouble.

[JustinBTE]

alright thanks man...im gonna get on that tonite and pop the new filter in and see how that goes....if thats not it then im running up to autozone and throwing on a new 02 sensor.

[carlover626]

I also forgot to ask what plugs you are using? Did you get the original AC Delco Platinnum plugs? I hear these engines eat up other plugs.
You will also need the disconnect tool for the fuel filter, and be careful not to break anything!

[DontPassTheFence]

The fuel filter is a PITA!! plan on working on it for a few days, and be sure to get the correct one to replace it. It isnt necessary to release the pressure in the fuel system before taking the fuel filter off, but also, you dont want to stare directly at the fuel filter, the fuel may drip or splash into your eyes/face. i suggest doing this in a cool garage with no direct sunlight, and plent of rags as well as a safe way to dispose of all the rags.

and keep an eye on the fuel filter for the next few weeks after you do this proceedure, if any connections are loose after you install the new filter, it may come apart during daily driving, so be careful

(thats what happened to me, :lol: - damn car died in the middle of traffic one day and it wouldnt start, looked under the car, and there was a tiny puddle of gas near the rear right wheel. Whoops! the fuel line popped off the filter)

[JustinBTE]

alright...i just got a haynes repair manual for all the N-bodys so it shows me step by step how to take the fuel filter off and replace it. When i went to get the new spark plugs months ago me and my dad went up to autozone to get them and the guy gave us the ones i got but im thinking he might not have gave us the platinums since the problem went away for a little while but is now back again so i might just get the plattinums before anything else...plus those are a cinch to change.

[carlover626]

I know that they are about 6 bucks a peice, so if you spent less than that, you could have the wrong ones. As far as the fuel filter is concerned, I wouldn't forget about it since these should be changed like every 30 thousand miles.
Skip the 02 sensor, I have a 97 with 93,000 on it and have no sensor problems. Just do the regular stuff and see what you get. Glad to hear you got the manual, if only I had a nice shop with a lift and tools and I would be set! :)

[JustinBTE]

ha...exactly...wouldnt we all love that though? yeah i've got the ac delco platinums in my car right now and im gonna put them on in the morning and then i'll wait a little while and then change the fuel filter too to get that done and over with....man that sounds like a pain to do after I read the manual to see how to do it...

[carlover626]

At first thought you would think the FF should be easy!
Yeah, just spray a little WD-40 on the connections that will come apart. I am not SURE that will help but if it is the original the connections could be bonded together, it can't hurt.
You will also want to get the disconnect tool from AutoZone or something, mine was the wrong tool (guy at the auto parts store sold me a PLASTIC, FORD disconnect tool that was in peices before my Fuel Filter was replaced).
And de-pressurizing the system is not a must, but I found it to be fairly easy, just unplug the electrical connector (for lack of a better word) which is under the car where the tank is, and start the car. It won't run long since the pump is off, and once it dies make sure to disconnect the Black (-Negative) cable at the battery.

[JustinBTE]

well that doesnt seem too bad. the other day i just put in the new plugs and i came to realize the old plugs were bosch platinums and not the AC delco platinums. the car runs fine now. but i think i'll still change the FF cause they say every 30K miles and i havent changed it since i got the car and that was almost 40k. After getting the new plugs in the car has all its power back and runs so much smoother now. I guess that was just the problem.

[skateswitch97]

myine does that too, but its auto, usually does it coming out of school parking lot, very embarassing, anyways i usually just tap the gas, but some times as you have all discribed you hit the gas and nothing happens, then it finally kicks in, you drive alittle it quits doing that, at one point i had to gas it when stopped to keep it running or it would idle like a drag racer(you get the picture) we took it to the shop that did the timing chain and thye adjusted that but i still get the short hesitation and crap everyday, that sucks didnt realize it hapens to everyone

[skateswitch97]

by the way its not the plugs mine did it before and after, never made one bit of difference, never lost any power from them either, actually seemed a tiny bit more responsive

[carlover626]

How many miles do you have? I just passed 94,000 and I am confused more and more everyday. I am still wanting to try Seafoam and see what that does if anything.
Have you had any problems with the Bosch plugs?

[Lash]

Bosch plugs sucks. Avoid them at all costs.

[JustinBTE]

well i realized my problem wasnt neccesarily my plugs...after i changed them the car ran perfect then out of the blue one morning heading up to campus after the engine got warm it sputters horribly...And now i cant get the car to rev higher than 2K on normal speeds or 3K on highway without it sputtering...And once it sputters it just wont go anywhere...im guessing now its my 02 sensors but im taking it up to a shop saturday morning to run some tests and see what it acutally is...

Does this sound familiar to anyone?

[JustinBTE]

nevermind that last post...my spark boots that connect the plugs to coil pack were bad...one of them had deposits on it and the other was cracked in half inside of the plastic housing...runs perfect now for under 20 bucks

[carlover626]

Well I guess I should have changed those boot myself! :)

[Trunks]

I have the same problem, and havent been able to get the ff off. Going to try to get it off again tonight and see if its the prob.
Except mine idles rough and when driving it cuts out and i have to let off the gas and then get back on it. I also have a 97 2.4 GT.

[carlover626]

Get the fuel filter done and see what it runs like. It could also be the plugs (what kind do you have?), or coil pack?
Also check your air filter.
Is your engine light on?

[Trunks]

It was for a week then went off. I think the plugs are AC Delco not sure though. The filter is clean also.

[carlover626]

DId you get the codes read when it was on? If you changed the plugs I would make sure they are AC Delco's, if you haven't changed them and they look worn, I would. But only use the stock AC Delco Platinum Tipped plugs (and Anti Seize on the threads!), others can cause problems. Look at the Coil Packs, plastic cover under the 2.4 Twin Cam cover you take off to get to the plugs. If it has dust trails, it may be cracked and need replaced.
What is your milage?

[JustinBTE]

also make sure you check your boots too...that was my problem all along and those threw my whole engine off and was fouling out plugs.

[carlover626]

Okay well I was F'n with my car over last weekend and I noticed a 5 inch log hose running from the Exhaust Manifold to an electrical connection near the IAC Valve. (all of this is located where the IAC Valve is on the throttle body). The hose was old and cracked at the ends where it connects and as I moved it with my car running it did the hessitation thing bad. After posting this I have found that this is a tube for the EGR line.
Well since I didn't want to really screw with it too much I just took off the tube, and taped the whole thing up with electrical tape to stop the leaks till I get the right replacement. (sorry no pics) My car isn't doing hessitating as much, and I can tell it was helpful.
You may all want to look around for vaccuum lines that are old and cracked and replace them, I am thinking this is the cause of the idle fluctuation.

[Bpow]

I've replaced all my vaccuum lines and I still can't figure this damn car out. Going to have the fuel filter replaced next week because I stripped the nut :s.....it was all rusted together thanks to Michigan for loading the roads with salt during winter.

[carlover626]

Yeah I get the damn salt and crap too, lol.
I was lucky changing mine out (FF), but it was not by procedure! :)
What other vac lines did you replace?

[Bpow]

the emission lines, lines running to and from the charcoal cannister, lines running to the brake booster. Had the filter done now, the car runs with much more pep.