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Hey ECG Forum members, happy new years.
I’ve returned with a new problem: I was driving to work today on the highways, foot on the pedal at 2500rpm max (got a light foot) doing 40mph. As it climbs to 45mph rpm drops to 1500 and then picks up to 2400 and then drops again, the needle looked like a pendulum going back and forth. The whole time my foot was still lightly on the pedal. While the needle was going back and forth, the car was jerking a bit hard when the needle moved. I checked my transmission fluid as this is an automatic and it was fine. What could the problem be?
In the meantime I will be taking regular roads to work doing only 40mph max. Thanks for reading and hope you can help.
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Issues under engine load tend to be ignition related.
http://www.youtube.com/user/EricTheCarG … AOmUjAjNjE
The above video may be of some assistance to you that Eric made.
When was the last time the vehicle had a tune up?
Any CEL?
Interesting that the links did nott work. No one has had an issue before unless its because i’m logged into my Youtube account.
Ill try again –
This is for ignition voltage leaks –
http://www.youtube.com/watch?v=x-U9WqJf … e=g-user-u
Power balance test –
http://www.youtube.com/user/EricTheCarG … AOmUjAjNjE
Excellent posts guys. Yes if you have a check engine light it would be good to know as that would be our best clue to help you, I also agree with checking for voltage and vacuum leaks just to rule those out if nothing else.
Check wires that go near hot areas, exhaust manifolds, catalytic converters, engine block. Also look for wear on wiring bundles.
Quoted From dreamer2355:
Interesting that the links did nott work. No one has had an issue before unless its because i’m logged into my Youtube account.
Ill try again –
This is for ignition voltage leaks –
http://www.youtube.com/watch?v=x-U9WqJf … e=g-user-u
Power balance test –
http://www.youtube.com/user/EricTheCarG … AOmUjAjNjE
On the power band test, I would disconnect the spark plug wire at the spark plug end correct? And to check spark I would hold that end close to the valve cover (since it’s metal right?)
Thanks for the videos by the way, just today I began to suspect the worst. The CEL is not on, sorry if I didn’t mention, I thought that would be an obvious thing to state if it was on but no light here.
For the power balance, you could also try disconnecting the fuel injector at each cylinder one at a time, so you don’t flood a cylinder. If you are cancelling spark, then yes, disconnect the wire at the plug end. For a spark test, I would use a high voltage spark tester. They’re cheap.
You will probably end up with a check engine light, so be prepared.
Quoted From dreamer2355:
Issues under engine load tend to be ignition related.
http://www.youtube.com/user/EricTheCarG … AOmUjAjNjE
The above video may be of some assistance to you that Eric made.
When was the last time the vehicle had a tune up?
Any CEL?
About 2 or 3 months ago the transmission oil was changed. I changed the engine oil and filter a month ago. Video link did not work by the way. What’s CEL?
Quoted From dreamer2355:
Also to add, when was the last time the vehicle has a tune up?
The car was bought used and has been owned for a year now.
4 months ago there was the said transmission oil change (did not change the filter though)
Periodic 10-40 oil changes
Air filter
I’m about to change the spark plugs and wires soon. I looked at the plugs 2 months ago out of curiosity and they were a bit black, kinda burnt.Hey I was reading around other site (gasp) and I was wondering if driving with overdrive gear off and seeing if the problem still occurs would mean anything. What do you all think?
It could indicate that the overdrive clutch pack or band was slipping, but I have a feeling either might be used for other gears. I don’t know the trans, so I can’t give you a definite answer. However, if this did solve your issue, you may have internal transmission problems, which would be bad news.
What did the other site suggest would be a fix if you turned off the overdrive and didn’t experience the issue?
I would not recommend driving around without over drive. The whole point of that gear is to reduce engine RPM’s, reduce drive train noises, help reduce engine wear as well as to help increase fuel economy.
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