Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









Search Auto Parts

Intense gas pedal vibrations at high rpm under load in my 2003 Mitsubishi eclipse spyder gs 2.4L


  Email This Post



TrevorJBauer
New User

Jul 14, 2020, 3:11 PM

Post #1 of 8 (251 views)
Intense gas pedal vibrations at high rpm under load in my 2003 Mitsubishi eclipse spyder gs 2.4L Sign In

I have been trying to fix my car with my father's help for the past month or so. Usually I go to a mechanic but the problems were with the engine and all local mechanics were charging way too much.

A little history:

My car lost its timing belt. I got the cat used so I did not know the belt was due. Upon opening the rocker cover, it was clear that all the valves were up when it blew (or at least we think it was clear. No damage was visible but we're by no means mechanics) so we decided to try replacing the belts and seeing what happened. Now my father did moat of the disassembling and I helped putting the belts on. The car fires up! So excited! I tried driving a little (just running some small errands) and realised all was not well. I noticed jerking from shifting gears and vibrating at high rpm. "crap maybe a valve is bent". So I did some research and found it could be that I need an oil change, need to put a proper gasket on the rocker head, or need a new motor Mount. Okay fine did all those (one Mount was broke) and it fixed the jerk! Go for a test drive and it drives normal until you get ~1000rpm from redline. At this Point the gas pedal vibrates violently.

The symptoms:

Car drives fine until ~1000 rpm from redline. At this point the gas pedal vibrates violently, but the car will still increase rpm. There is no shaking at lower rpm. Speed does not effect the shaking, only rpm. Happens in first and second gear, I cannot test third and fourth as I don't drive that fast on public roads. Idle seems fine. Doesn't happen out of gear.

What I've come up with:

By researching and talking to friends I've found This couldn't be a wheel alignment, or it would happen at all speeds and get worse as I go faster. There was a guy who had a Ford gt with similar symptoms and it was in need of a transmission alignment. I have no idea if this is a thing but I hope isn't the problem. I don't see how the transmission could have been misaligned Anyway. One of the timing gears is off by one tooth. This could be the problem but I don't know if it would cause shaking at high rpm and we double and triple checked it. I wouldn't love pulling it apart again to check again but I may have to. A valve could still be bent I suppose but again I don't know if it would do this. The forum about the Ford gt also mentioned the engine could be getting starved of gas, but I don't see why it would be now when it was fine before. Unless of course the timing is off by a tooth and it's spitting gas at slightly the wrong time.

I'm pretty deep in this project now and really just want to drive my car. My father is fed up and wants me to just drive it but I don't feel safe. I appreciate any help/input/ideas anyone could provide. Thank you.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Jul 14, 2020, 3:30 PM

Post #2 of 8 (249 views)
Re: Intense gas pedal vibrations at high rpm under load in my 2003 Mitsubishi eclipse spyder gs 2.4L Sign In


Quote
One of the timing gears is off by one tooth.


That's not OK. The belt can only go one way with no margin for error.

This engine also has a balance shaft belt that has to be installed exactly correct of you get a vibration.

This is an interference engine so if the engine was running when the timing belt let go, it's virtually impossible to NOT have bent valves.

I suggest the first thing you do is a complete compression test.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Jul 14, 2020, 3:48 PM

Post #3 of 8 (243 views)
Re: Intense gas pedal vibrations at high rpm under load in my 2003 Mitsubishi eclipse spyder gs 2.4L Sign In

Quote: ">
My car lost its timing belt. I got the cat used so I did not know the belt was due.<"


That would be #1 thing I'd verify or be just doing it. Do know the things are by miles OR time now that your car about 17ish years old can easily out cost the car now.


Do the compression test and the bet is bent valves lucky it runs and now a tooth off admitted this isn't working out to save a buck DIYing it and being wrong twice now on the thing.


Real mechanics would look like a steal about now but it happened see what you find for compression will be the answer,


Tom



TrevorJBauer
New User

Jul 15, 2020, 5:06 PM

Post #4 of 8 (207 views)
Re: Intense gas pedal vibrations at high rpm under load in my 2003 Mitsubishi eclipse spyder gs 2.4L Sign In

Im sorry I think you misunderstand. I was just saying the timing being one tooth off could be the problem, but my father is adamant that the belts are on correctly.

I have done a compression test and all four cylinders were 180psi.

Since the engine is not the problem, is it possible that there is something that was removed to install the belts that needed to be torqued to spec and was not?

I've also noticed there is a metal grinding noise when I rev up past 2000rpm. It exists only at 2000 rpm and goes away above and below that number.


TrevorJBauer
New User

Jul 15, 2020, 5:08 PM

Post #5 of 8 (203 views)
Re: Intense gas pedal vibrations at high rpm under load in my 2003 Mitsubishi eclipse spyder gs 2.4L Sign In

Im sorry I think you misunderstand. I was just saying the timing being one tooth off could be the problem, but my father is adamant that the belts are on correctly.

I have done a compression test and all four cylinders were 180psi.

Since the engine is not the problem, is it possible that there is something that was removed to install the belts that needed to be torqued to spec and was not?

I've also noticed there is a metal grinding noise when I rev up past 2000rpm. It exists only at 2000 rpm and goes away above and below that number.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Jul 15, 2020, 5:12 PM

Post #6 of 8 (201 views)
Re: Intense gas pedal vibrations at high rpm under load in my 2003 Mitsubishi eclipse spyder gs 2.4L Sign In

What about the balance belt?





~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



TrevorJBauer
New User

Jul 15, 2020, 5:31 PM

Post #7 of 8 (197 views)
Re: Intense gas pedal vibrations at high rpm under load in my 2003 Mitsubishi eclipse spyder gs 2.4L Sign In

My father is adamant that the belts were put on correctly, but I am still not sure. It is so much effort to access them that I am hesitant to tear it all apart again.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Jul 15, 2020, 5:40 PM

Post #8 of 8 (195 views)
Re: Intense gas pedal vibrations at high rpm under load in my 2003 Mitsubishi eclipse spyder gs 2.4L Sign In

Then I guess you had better take it to a professional for diagnosis. We can't experience the problem or confirm anything from here.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.







  Email This Post
 
 


Feed Button




Search for (options) Privacy Sitemap