I have just had a service on my other half's Mr2 SW20, they pointed out that the cam belt would soon need changing, so I bit the bullet and told them to go ahead. Two and a half days later they said that it was ready, having fobbed me off with the excuses that the mechanic hadn't done one before, that he wasn't happy with it, and that he had some trouble with the timing, and finally that they had found the cambelt to be one tooth out.
When I drove the car home it was a pile of c..p, with no accelleration at all, the 1.4 deisel Yaris that they had loaned my wife had ten times the acceleration of the MR2. It was taken from the Toyota main dealers compound just before closing time, otherwise I would have driven it straight back there, as it is I will take it back first thing in the morning. I suspect that attempting to start it with the timing out, may have damaged something, possibly some valves and caused a slight compression loss. Does anyone have any other ideas as to what would cause this dramatic loss of power and acceleration, a rough check of the 0 to 60 time showed it to be about 15 secs, a lot less than it used to be. What is the official 0 to 60 time, I would have guessed at well under 10 secs?.
Cheers
Bill W.
The MR2 Turbo at stock in good condition acceleration is about 0-60 in 6 seconds.
If the mechanic was off by one tooth on the cam gear/crankshaft alignment-it would run very rough at idle. I'm don't know that you could have even driven it off the parking lot.
A vacuum line, boost leak or worn ignition components could also be responsible.
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I'm pretty sure they are non-interference motors so I doubt you have any damage in the head. Plus if there was damage in the head it would most likely be making noise still. I'd take it back up there and tell them what's wrong with it. They might have left something else loose.
I wouldn't even drive it back to the dealership. The car doesn't drive properly and it is too dangerous to drive it back to the dealership. You should call them up and have them arrange a tow truck...of course, at their expense.
I took it back at 08:30 this morning, and after they had driven it and agreed it wasn't running correctly, I spoke to the service manager and the dealer principal, who apologised for the problem and assured me that when I get it back it will be running like an MR2 should. I await their completion with anticipation.
I'm pretty sure they are non-interference motors so I doubt you have any damage in the head. Plus if there was damage in the head it would most likely be making noise still. I'd take it back up there and tell them what's wrong with it. They might have left something else loose.
It IS an interference motor. If the Timing belt breaks, the cams and valves stop in thier tracks while the crank continues to spin. ugh...
But you are right about the rest.
It IS an interference motor. If the Timing belt breaks, the cams and valves stop in thier tracks while the crank continues to spin. ugh...
But you are right about the rest.
I knew there was a reason I like the 4AG motors better :P
I knew there was a reason I like the 4AG motors better :P
I hear ya.. When I blew my head gasket last year, I wasn't sure at the time what the real problem was. I feared a broken timimng belt and shattered piston(s)..All engines should be non interference...oh well.
non interference motors are only protected if the timing belt breaks... if you install one and the timing is too far off you better believe your gonna bend some of your valves...
and a motor can run 1 tooth off... how much more than that i dunno... but i've seen them run one off.
I'm not sure how many teeth off you can run a T-belt, it most likely depends on how high you rev it as well, or if it's a VVTi motor, which doesn't really apply to the older gen MR2's.
non interference motors are only protected if the timing belt breaks... if you install one and the timing is too far off you better believe your gonna bend some of your valves...
and a motor can run 1 tooth off... how much more than that i dunno... but i've seen them run one off.
When I put on my new timing belt, I was off 1 tooth. It cranked up easily, but ran really rough. of course, immediately I knew i was off.
I'm curious though-what exactly on a non interference engine prevents the valves from hitting the pistons when the belt breaks? I would think all the valves would have to remain in the closed position.
Just for my education....
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