Hey all!

I have just bought a 2nd hand 1996 Corolla BZ touring Wagon. So far, really impressed except a small acceleration problem. When I need to accelerate a little harder than normal (like getting into heavy traffic) the car seems to loose power and sometimes shudders. If I accelerate normally, or put my foot down hard and make it drop down a gear, it's fine. Its only seems to happen in medium-hard acceleration (even once the car is moving at speed and I want to speed up a bit more quickly).

I have already changed the plugs to Iridum plugs and put in a new airfilter. I have been doing a bit of research and it sounds like the injectors may be clogged.

Any thoughts or ideas? Any help would be gratly appreciated.
Thanks all!
LionsLord

Hey All!

Good news! I put a bottle of total gas system cleaner though my car, and topped it up with gas from a different station, and my car is running much better! Tomorrow will be the big test though. I will take it on a business trip of about 160km total. Thats 80km to and 80km from where I need to go, and 70km of each way will be on the expressway at about 100km/H (about 60m/H). After that, the cleaning solution will have gone through my gas system for a fair while and I will really know if the problem is solved!

Wish me luck!
LionsLord

Aghh!!! No luck all!!! Still having problems with the car.

It had a good run today on a business trip, but still have problems. Ok here are the symptoms in more detail.

1) When accelerating from a almost stop, the engine seems to put out a dull combustion sound. Its kinda hard to explain, but its like its trying to accelerate, but the sound of it is dull. Its kinda like the same sound as when you run out of gas.

2) sometimes the car is a bit jerky and the engine sound will corrospond to that jerking. The engine also seems to make a vibrating sound.

3) sometimes i can hear the tappits ratteling.

4) The car seems to be reving (but in the dull way mentioned in 1) but not really accelerating.

I guess its kinda all like when you run out of gas, except speeding up, not slowing down. Thats about the best I can describe it. From that, I would guess it has something to do with the gas system.

As I mentioned in a previous post, I just bought this car 2nd hand and it has 78,000km on the dial. I have already replaced the spark plugs (with irridium plugs) and the air filter, and have run a tratment of total gas system cleaner (still going though with this tank of gas, but already 200km, about 120 miles thought the treatment).

What does eneryone/anyone think? Possibly the timing belt? Any other ideas?
All responces appreciated!!!

Have you tried changing the spark plug wires, or having the distributor checked?

Sounds like the fuel injection system to me. Have you had the car in for a major tune up since you bought it?

I have a '94 Corolla... standard model with 1.6l engine and 3 spd. AT. I commute 150 miles 5 days a week and I sure am glad my car gets around 32mpg!! But I have the same weird problem with a "vibration/studdering" when accelerating. Now the car never had much acceleration to begin with - bought it a couple of years ago with 48K miles on it - now up to 105K. The vibration is not something I recall early on... it seems it's come about in the past 3 or 4 months and may be getting worse. Now being as I have been a professional Toyota Technician in the past and still do most of my own auto work let me share what I know.

I added a K&N cold air intake... not the stock one that would fit into the OEM housing (I removed that) but I did a custom install... in reverse order starting at the intake housing is the original black plastic tube with "mini-muffler". Into that I have a 3" dia. alum. cold air intake tube and on the end of that is the cone shaped K&N. I drilled a hole in the bottom of the "mini-muffler" and using a rubber grommet that is where the "air temp sensor" is now located. This setup definitely gave the car some more power, but it's still not great.

New platinum plugs installed. No engine warnings. Mechanically I believe all is quite sound. Suspension seems tight. Alignment done 6 months ago, doesn't pull. Thought maybe it was my snow tires, but I bought 4 new rims and have new Dunlop All Season Radials on now. Still same vibration. Changed transmission fluid 2 weeks ago along with the filter and differential fluid.

When gliding no vibration, or at high speed on expressway vibration much less noticeable. But with normal to heavy acceleration very obvious, but less so feeling it in the steering wheel. Feels exactly like the engine is missing but at a set (high) pace, not erratic. I have tested the fuel pressure sensor (idle increases when disconnecting vacuum hose). I've done a visual and hand check of all other connectors. All seem fine.

My final assessment - leads me to believe it's related to the spark plug wires/distributor... will find out this weekend I hope.

I'm having the same problem with my 2000 Corolla manual shift. At a light, for example, I hit the gas, take my foot off the clutch and nothing. It simply sputters through the intersection. Also when on an on ramp while trying to accelerate it really begins to sputter and jolt....as if it's not getting any fuel.


I've had it to 2 different mechanics that specialize with Toyota and neither can find anything wrong. I put in some STP gas treatment and it helped a little bit but not 100%. When I get the chance I'm going to try to remove the fuel filter and see if I can figure it out on my own. But if anyone has any suggestions I'd really appreciate any help.

I posted earlier about the "studdering" problem - '94 Toyota Corolla... can say changing wires, cap and rotor sure helped, checked and adjusted timing, installed new fuel filter too - definitely more power, but the problem is still there. It's simply more defined now... under load/accelerating the studdering/wobble starts at 48mph to about 58mph, thereafter it goes away. Doesn't matter if I'm on a level road or going uphill, only when not accelerating is there no vibration/wobbling/studdering, etc. But soon as I accelerate between 48 - 58 mph the studdering occurs. If I go up a steep hill below 48mph even with the pedal to the floor the engines roars and there is no problem. It simply doesn't make sense... if it were tires, or suspension it would happen even if not accelerating... if it were a bad plug(s) would run rough at any speed, esp high speed. have checked for vacuum leaks and anything else that is obvious... only thing left to do is pull out the Volts/Ohm meter and start checking the electrical/emmisions devices. Maybe a bad throttle position sensor, egr valve, etc. Will also have to find my fuel pressure guage, or buy a new one. Almost feels like it's just not getting enough gas. Open to ideas, as are others here with similar issues.

Well at least we can say this is a fairly common problem. It seems the change of gas has helped some. Perhaps continue to try that for a while longer. I'm interested to know how your vehicles are functioning otherwise? The gas mileage is still good? Anything else going wrong?

Update... well I made progress since I last posted... I had decided as you may recall that the problem seemed linked to emmision controls... I decided to try unplugging and replugging in the MAP sensor and the Throttle Position sensor... amazing, the latter seemed to fix the problem, for one day. The next day it studdered again, and again I unplugged TPS. Again... studdering fixed... only to return a day later. This is progress I think, since it never went away prior to that. Today I used a small plastic widget to give a very slight tilt to the four pins in the TPS... we'll see if that does the trick.

Thanks for the update. We'll keep our fingers crossed for you! I hope it works well this time.

Did you check the clutch? (IMG:style_emoticons/default/57.gif)

I resolved my "studdering problem" :) The solution was unexpected, pretty simple and I should have figured it out much sooner.

The simple fact is that although I had previously checked for mechanical suspension problems, I obviously didn't check as precisely as I should have or I missed the obvious. Initially when I used the old pry bar to check the front ball joints I detected no play. After stating it appeared to be the TPS connection was suspect, it turned out after believing that for a week or so that it really wasn't the culprit... so I went back to square one, jacking the car up and checking the ball joints once again. This time I detected a very slight amount of play on the driver's side. It was so slight I was at first hesitant to believe it could be responsible for all my problems, and to spend the $50 for a new one if that wasn't it, but the vibration was so annoying I decided that of the options I was considering, like changing the O2 sensor, TPS, fuel injectors, etc, that changing the ball joint was something I'd probably need to do sooner than later anyways, so I did. The difference was dramatic, but not complete. It had a definite effect - removing like 60% of the problem. Now that I knew there had been a suspension issue involved, I sensed somehow the other ball joint was bad too, even though I felt no play when using the pry bar on it, and I was right... when I replaced the other ball joint the vibration vanished completely. I then realized how because the engine isn't all that powerful, that when accelerating, it had caused the car to shake because of the bad ball joints. So simple!