My car "redlines" when I start it.
It is like the throttle is stuck.
In a previous post, I suggested something to do with th transmission was on the fritz. But that is most likely incorrect. After futher consideration it seems that my throttle is somehow stuck on wide open.
Any ideas??? Thanks in advance.
- Ben
Have you even opened the hood and looked? You have a 17-18 year old car.
It's entirely possible the throttle cable has worn to the point of sticking. You need to track down the cable and see if the end looks frayed. If what I'm saying makes no sense to you - call for a tow and have it taken to a shop (dealer or independent.) Running the engine at redline for very long is a sure-fire way to destroy the engine.
To answer your question - I been looking under the hood for the last few months, about every other day for one problem or another. The car has
230,000 miles. In the past few months I have - with some help - replaced the:Mass Airflow Sensor
Starter
Air Intake Manifold Gasket
The information I have received from this Newsgroup has been very helpful in most cases
Where my current problem is concerned, I have not yet noticed anything wierd about the throttle cable.
But I am reading the Bentley manual and find myself wondering if the "Idle and Full Throttle Switch" could malfunction and cause my engine to run at full speed (redline).
Or maybe there are other components, when failed, that could cause an engine to fun at full speed.
All responses are appreciated.
Thanks in advance.
- Ben
consideration
Your car can only possibly redline if the throttle is open and that can only possibly be produced by the throttle cable. There are no other actualtors / stepomotors in the car that can do this. It should be a relatively cheap fix - I hope!
No, that's not possible. To run at that speed it needs air, which is provided by the throttle valve being physically open. Sensors and switches can alter the amount of fuel but not that, not on an older car anyway.
You need to find where the accelerator cable goes to the throttle and see what is going on. You can physically move the throttle valve by hand to achieve the same effect as pressing the pedal. Just follow the air intake through to the throttle body and find where the cable goes in. Should be very easy to see.
The cable could be stuck, a return spring could be broken, and although it sounds daft it's not uncommon for the pedal to get wedged down against the floor mat.
It would be way easier if you guys would use one (bottom) posting style.
If your car has cruise control, it could be the CC motor/cable.
The other thing I haven't seen mentioned is crankshaft position sensor. Don't know if the M20 had one... Wouldn't think that that would cause over-rev (usually start/run problems.)
FloydR
I don't believe in top or bottom posting style. I believe in adding comments where they might be understood.
Could, but I've never heard of one actuating itself. I think he has to get to some elementary checks - like is the throttle body stuck wide open? Is so - why? He mentioned he's replaced the intake manifold gasket(s) - so he should be familiar with the area, and there is always the chance he messed something up doing that job.
CPS has nothing to do with an over-rev condition. Nothing. Guarantee.
I agree. If I am replying to a lengthy post that should not be snipped, I'll top-post rather than require the reader to scroll down past a message he has probably read earlier.
OTOH, if I'm reply to just a 2-line portion snipped from a larger message, I'll bottom-post.
The whole point us readability.
Other than personal preference, why? Please don't start the debate, just cracking a funny..
The crank position sensor is irrelevant in this matter as is the cruise control. The throttle is being held open probably by a frayed cable or just worn parts. Grab the linkage and work it back and forth. If it doesn't move from one extreme to the other without sticking, you've found the problem.
"...should not be snipped..."
Well, there's your problem. It's about *editing* for content, not wholesale *snipping*.
A lengthy post really needs to be edited down to the essential part to which you are responding. Remember, we read the original post; we don't need to read the whole damned thing again. The trouble is, it takes a little time and thought.
I'm with you, admin. I don't think the Cruise can cause this, and I think there are some elementry checks for stuff that is binding/bound up. As for missing something on the earlier repair, perhaps the throttle return spring is on backwards.
What sucks is that some people witll top post.
Some will add in the middle where it makes more sense.
And some will post on the bottom.
I like to post where it makes sense. This is at the top, in the middle, or on the bottom. It always is determine by what has been said before me, and how. Readability is key.
Floyd was addressing the point that one guy posted on the bottom, and the next reply was a top post. This gets tedious.
DING DING DING We have a winner! The throttle is being held open, and my guess is the return spring (since the OP confessed to replacing the intake manifold recently).
Grab the linkage and work it back and forth.
Excellent test. It will not only help isolate the problem, it will cause him to look closely at the mechanical interaction of parts that are there. I'd also suggest working the throttle pedal by hand.
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