The car starts and idles. It's an automatic. The fuel system checks out(It has about 15 psi at carburator). Engine code said 13(oxygen sensor). I replaced that. I messed with the timing, checked to see if the sparkplugs were firing, and the compretion. I'm stumped, somebody please help.

and people say geos are fast :nono:

Sounds like the timing belt slipped a tooth. Take it off, and re-time it. 1 tooth can make a world of difference. What PSI are all the cylinders at? If any one is below 135psi, that cylinder is most likely dead. (burnt exhaust valve 99% of the time)

It might be your catalytic converter they will sometimes get plugged up.

This will cause way too much backpressure in the exhaust system; it will idle ok but try to get anywhere and your hosed.

It might be your catalytic converter they will sometimes get plugged up.

This will cause way too much backpressure in the exhaust system; it will idle ok but try to get anywhere and your hosed.

Sorry to revive a topic from the ages past but I was just at a muffler place and the muffler guy, Joe, kept going on about how he'd never heard of a cat that would get plugged up enough to let the engine idle and yet bog the engine down on the street.

I knew he was wrong so I insisted that he replace the catalytic converter, which he did. When he got it out it was full of melted shards of metal and gobs of black soot. Is this problem unique to the metro? Surely other engines bog down when a catalytic converter plugs up? Or is it that the G10 is so small any changes in backpressure are noticeable?

i had one doing same thing, would run ok till you got up to about 40 then not go any faster, turned out the fuel pump was bad, pressure tested fine just like yours but the volume was to low. take the return line off where it goes to metal hose on firewall (its the smaller fuel line, big one is pressure side) stick it in a gas proof container and start the engine for a moment. if pump is good you will get a good stream of gas coming out of the return line. on mine if just got a little trickle. replaced the pump and now its fine

same thing happend to my 91 geo. Wouldn't go over 40 mph, turned out to be the fuel pump.

How does the engine run at 40mph, does it miss or no more 'get up and go'? If it is missing I would agree it is a fuel pump, but if it has no guts that is a differant matter entirely.

How does the engine run at 40mph, does it miss or no more 'get up and go'? If it is missing I would agree it is a fuel pump, but if it has no guts that is a differant matter entirely.

My car was returned to full power when the cat was replaced. I would think that if it was a faulty fuel pump that the engine would miss and behave as if it was running out of gas.

I had exactly the same problem with the cat on my '86 Samurai. Confused the hell out of me until I figured out what it was.

After having the cat changed out, we found out what had happened- a large chunk (or perhaps all of it) of the catalytic material had broken loose and was just floating around. Enough exhaust pressure would move the material and plug the cat up. Backing off revs would allow the material to fall away again, and the engine would run fine.

-Pink

How long should the CC last in a geo? I had mine replaced November of... '03 - it should still be good, right?

My car has been having issues, and we are assuming that it is the fuel pump. (try to accelerate and it dies)

Just checking..
thanks!

Christy and her '91 Geo

christylee2@gmail.com