94 automatic poor acceleration

[rickj66]

Hello, my 94 metro automatic (139K) has really low power and accerlation when starting from a stopped position. this just started suddenly 3 wks ago but seem to be getting worse. i can shift manually into a lower gear and get the rpm of the motor and increase speed and then shift back into drive and it runs fine. tune up was less than 8 months ago, checked rotor and checked for vacuum leaks but have not found any. replace pcv valve when i found a chunk of carbon blocking the inlet. cleaned some debri out of the egr ports and replace the gasket on egr valve. the diaphram seems to me moving freely.
thanks

[geozukigti]

If your EGR was plugged, you probably burnt an exhaust valve. Do a compression check. I bet you're running on 2 cylinders.

[Valero]

Valve problems dude. I also have a 94 automatic with 144K, had enough power when accelerating to past little old ladies, it got worst, took the heads off, found two exhaust valves that were not longer round (at their face). I went the long way, replaced piston rings, all gaskets, both set of valves and lifters, and voila! the thing is better than new. Lots of work but I LOVE IT !!!!

[rickj66]

thanks for the information. not what i wanted to hear, but at least i have a place to start. appreciate your feedback

[kltuck]

I dunno? I recently changed a tranny because it started the same way and finally ended up with the tranny not moving at all. The problem went away right away. But now, after a month or so, started no power when starting out again. Like you, I can manually shift into low and have really good power. SO, I kind of doubt the valve theory. Although every Metro has this problem. If it was the valve/head would I be able to manually shift and have it work fine? Book says you can adjust the cable and get it to downshift correctly but after 2 hours tonight I dunno (Again.)

[zerocool1014a]

yea.. the bad thing about geo's is their habit of burning valves.. but the good news is that even if it is.. you will either 1 have to rebuild the head or 2 you could and probably for about the same price get a rebuilt engine for it and have a pretty much new engine.

if its not the engine i would deffinately check the transmission, my sister had an automatic I have a manual and hers was loosing power and shortly after that it started having problems shifting correctly... no supprise that the car was loosing power tho.. i mean she did take a steep grade with a blown water pump, and a quart low on oil..

[geozukigti]

I think you're thinking of the wrong valves. The valve body in the tranny has nothing to do with the engine. No matter how you shift, of you have a burnt valve in your engine head, you're gonna lose compression and have a dead cylinder.

[MArp]

Just experienced the same problem. Took the car to AAMCO transmission, hooked the car up to read the electronic error codes and located error code "p o 705"

According to the software it is a shift sensor switch. The factory is very proud of these switches. $502.00 I have not gone to work on the "fix around" for this yet, but I will. I feel very strongly your problem is the same. I can shift the care from L1 to L2 and then Drive with excellent performance. The recommendation from AAMCO was to change the transmission fluid and pickup screen and drive the car by shifting. They were very honest and recommended driving the car that way until the very end.

[GM Line Rat]

Originally Posted by MArp

Just experienced the same problem. Took the car to AAMCO transmission, hooked the car up to read the electronic error codes and located error code "p o 705"

According to the software it is a shift sensor switch. The factory is very proud of these switches. $502.00 I have not gone to work on the "fix around" for this yet, but I will. I feel very strongly your problem is the same. I can shift the care from L1 to L2 and then Drive with excellent performance. The recommendation from AAMCO was to change the transmission fluid and pickup screen and drive the car by shifting. They were very honest and recommended driving the car that way until the very end.

1st off, this original thread is from 2004....However, the info shared is always good but the chances of the original poster responding are slim... Up until last Summer, I had a 94 Dr Metro that did this very same thing....Sometimes. I could drive the car for days and it would shift just as it should then, as I would get off the Hwy and come to a Stop...The car would be in 3rd gear (Drive) instead of starting off in 1st like it should and I would have to manually shift the car until I got up to speed.....There's was NO problem with the engine....The problem was in the Auto trans. If I hadn't had a good friend who rebuilds trannys for a living....I would have just bought another JDM Auto trans and replaced it because of the Cost involved in the repair. He pulled the Valve body out of the Auto Trans and rebuilt it with new pistons, seals, springs and plates etc, then put in a new direct clutch solenoid in it also. I re-installed the valve body, changed the tranny filter and put new tranny fluid in it also.....I did the trick!..... Never had the problem again.