Takeoff power loss, need help bad!

[markjs]

My 1990 Mitsubishi Mirage, 3spd A/T, 140K Miles, recently developed a problem taking off from stopped and dealing with hills. Basically it takes off into traffic painfully slow at first, then has normal power after about 10MPH. Also, if I try to start up a steep hill I can floor the gas pedal, but can't get much faster than walking speed, (we are talking very severe hill). On hills taken at speed I am pretty sure there is some power loss but it's not nearly as bad of an issue. It is not at all a transmission slippage issue, it's just as if all the car can do is idle up the hill despite maximum pedal. Also my gas mileage is significantly less than when I got the car.

I went to a very steep hill (which is where I first noticed that this was a real problem), and I tried to go up it. For a LONG time I could not get up to 10MPH, but just as it got above 10MPH it started to gain power, and at 15 it could actually accelerate slowly up the hill, and the faster I got the more power I had, though I ran out of hill. It seems to me that the only real problem area is on takeoff. If I get a running start at a hill it doesn't seem to be an issue.

Any power loss at normal running conditions is largely theoretical. I think there may be a little power loss but it's not significant enough for me to be sure, since I haven't even owned the car a year, and if there is power loss at high speed it isn't a huge difference. I do know that it did not have this problem on steep hills when I got it, or if it did, it has gotten radically worse.

I have NEVER gotten a "check engine" light, and I know the light works. I have a friend with a diagnostic computer I will have check it tomorrow, but I don't know if it even gives codes if it doesn't trip the idiot light?

Edit: I changed plugs, wires, cap, rotor, fuel filter, and air filter yesterday. I have not performed a detailed check of the vacuum system, but there are no obvious flaws, and it idles perfectly. The Timing belt was done very recently as well.

Through some searching on the forums I found some thought that perhaps a plugged cat can cause these symptoms?


I am REALLY DESPARATE here, I am poor, live in a VERY hilly state, and even though gas prices are way down this car should get better than it's current 20MPG. Any ideas will be greatly appreciated!

[drdisque]

Having an older car you probably don't have an electronically controlled transmission in which case you probably have a transmission kickdown cable.

It sounds to me like the transmission is sticking in 3rd gear. I would check to see if that cable is hung up on anything or has become disconnected.

[markjs]

no it's not that. I am talking about starting up a steep hill from stopped. it kicks down fine, but I have since had reason to believe that the issue is that it jumped a timing belt tooth.

[markjs]

I now know what it is, but it's pretty horrific. Since it is an automatic we could not get the bolt that holds all the pulleys and the crankshaft sprocket itself to the crankshaft to have sufficient torque to stay in. It is listed as 62 foot pounds, but there is no way to hold the engine still easily. We ended up having to repeatedly put that bolt back in. I actually lost the original on a highway and was forced to drive several miles at high speed with nothing but belt tension and the timing belt cover to hold things together. The last time we put the bolt in, we used two kinds of lock washers and Loctite, and braced the engine through the camshaft sprocket using the timing belt to get the torque.

The thing never came out again, but the damage had already been done. We thought somehow it had skipped a timing belt tooth (since it is a round tooth type). The terrible reality though is that the vibration had destroyed the inside of the crank sprocket and the end of the crankshaft. See the crankshaft end has two flat sides of different sizes to keep it only able to be on one way, but now the inside of the sprocket has small half moons and the crank has small hills on the sides. I will most likely be without a car for some time to come.


We may be able to replace the crank sprocket at great trouble and expense and it will most likely work ok but technically the crankshaft needs to be replaced (although the damage is minimal enough I don’t think I will have further trouble provided I can get the damn bolt to stay in this time). The other small concern I have this time is the original bolt fell out on the highway and is long gone. We have gotten a replacement bolt at the hardware store, but I am somewhat worried about that even now….

Does anyone have any ideas about getting that thing to stay in this time? I mean I think we can get the needed torque, but now I am paranoid about the whole thing!

[DFBonnett]

Which Loctite (Color?) did you use? Were the threads totally degreased before using the Loctite? Ideally it would have been the #271 which is red.

[markjs]

Yes, red....