2000 626, 2.5L V6. 92K miles, new plugs, wires, fuel and air filter, tranny fluid changed. Today it's start bucking under the slightest acceleration, low power and a little sluggish. Tranny is shifting fine, so I don't think it's that. I don't believe the belt has ever been changed, according to the previous owner. Are these symptoms of the belt going bad? If not, any idea what it could be?

Joe

 

a timing belt's only warning is generally when it jumps time. most of the time, you aren't fortunate enough to get to that point.

in that case, however, the same things will happen. the only thing that you missed is the "little sluggish" part. it will barely move under it's own power without the pedal to the floor if you jump time.

check the fuel pressure before you go tearing off the timing cover. sometimes, the fuel pump or regulator will drop or raise the pressure just 1-2 psi and cause similar symptoms that you are experiencing. if the pressure isn't off, it's probably the timing belt.

is it idling alright? if the fuel pressure is low, it will idle odd. with high pressure or jumped timing, it could idle just fine but drive terribly. high pressure, by the way, leans towards a regulator.

 

I had similar ebola under the hood of my 626 2000 1,8 a couple of weeks ago. The cure was a "real classic". I had cracks in the vacuum hoses so the "air mass meter" or whatever its called in proper english got fooled. Runs like a charm with new hoses. Take a close look at the hoses would be my guess.

You should cange the timing belt and the wheel and spring that keeps it tight asap (thoug i think it doesnt cause your problem) In the finnish verison of the book you should change at every 90.000km, equals about 56k miles. Last time my spring was just seconds from worn of. It cracked in my hand when gently sliding it away. The belt looked like new.

 

Im only used to 4cyl mazdas but when they miss to fire on one cylinder they behave just the same. Would it be an idea to pull out the brand new plugs and have a look. If you have some cylinder completly left out the plug usually smell gas and the threads look dark and "moist". You did push the connectors of the wires all way down didnt you? Last time i used cheap "noname" cables and it it felt i had to push them all the way down to the crankshaft before they connected.

Best regards from the Finnish forests (hoping for a cheap solution! )

 

The idle is fine, once it gets going it just chugs along.

I'll check the vacuum lines for cracks, but my luck is never that good! Nothing cheap about plug wires for this car, couldn't believe the prices! I'll double check everything. Thanks guys!

Joe