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what kind of problems would you notice if ur timing was off? whenever i start out in first gear i get a dip in the rpms like itll go up to 3k really fast then itll fall back down to 2k then go back up and start going. its really weird not sure what the problem is, my engine cannot keep a constant rev no matter what itll rev up then down never steady ever since i bought it.

replaced: disty cap and rotor, plugs, wires, new intake, coolant sensor, adjusted the tps, pcv valve, alternator, radiator, o2 sensor, fuel filter, water pump. its got 104k on it now its a 1.6 B6 dohc, stock everything else

Bumpysbro wrote:
replaced: disty cap and rotor, plugs, wires, new intake, coolant sensor, adjusted the tps, pcv valve, alternator, radiator, o2 sensor, fuel filter, water pump. its got 104k on it now its a 1.6 B6 dohc, stock everything else

i had the same problem when i had my 4 cyl, i had a bad MAF.
The fuel switch inside the maf wasnt making good contact.


what year is your car??
you have vaf or maf? plastic round one or the alluminum queer one?

It does sound to me like a fuel problem, I wouldnt mess with the TPS too much either.

Did you rule out vaccum leak - I think you have to connect a vaccum gauge to the intake (i am not sure how/where) and rev it up and see if theres any wild fluctuations in vaccum readings.

There is another fuel filter inside the gas tank that could be clogged up.

You can also try using few cans of fuel injector cleaner (seafoam) to clean the injectors and intake manifold

MOSES wrote:

Bumpysbro wrote:
replaced: disty cap and rotor, plugs, wires, new intake, coolant sensor, adjusted the tps, pcv valve, alternator, radiator, o2 sensor, fuel filter, water pump. its got 104k on it now its a 1.6 B6 dohc, stock everything else

i had the same problem when i had my 4 cyl, i had a bad MAF.
The fuel switch inside the maf wasnt making good contact.


what year is your car??
you have vaf or maf? plastic round one or the alluminum queer one?

It does sound to me like a fuel problem, I wouldnt mess with the TPS too much either.

hmmm ya thats what i was thinking arent they expensive? mines the plastic round one, lately everytime i start it let it run and turn around it just drops to almost dying but then i kick it up by reving it. and ya i ruled out vaccum leaks...

Well you said you changed out the water pump, you had to have seen the timing belt when you did that. Was it loose or worn?

ya it was loose by maybe 1 teeth but thats it, we retightended it since, i seem to think it is a timing issue, lots of black carbon around my tail pipe and bubbling sounds...my bro says the same thing and to get my idle fixed. thnx for the help ima take it in wed and get it tuned up and see what happens.
Jon

chec head gasket..where are bubbling noise soundscoming from?engine or out tail pipe?did car overheat befoe changing waterpump?

ya it overheated 2 times, once before we replaced the water pump and then again when my radiator blew, the sounds coming from the engine but today we did a compression test: 120, 85, 85, 90 but in the last one we found radiator stop leak so which means the coolant is seapin into the oil. head gasket?

yes,and have it pressure checked and chec to see if its warped.it will run nice again,