Engine Problems

666raCing · Post by **666raCing** » October 22nd, 2006, 10:37 pm

My friend, who is a mechanic was fixing my brakes the other day and took it out for a test drive when he was done. When i got it back, he said that it was a little sluggish and should go much faster for a little ar with a V6 in it. Can anyone suggest some problem areas they've had with this or some suggestions as to what may be the problem?

Im thinking the compression is wrong.

max kl · Post by **max kl** » October 22nd, 2006, 11:22 pm

that is a rather vauge statement. dyno or 1/4 mile numbers would help determine if you are underpowerd.
the stock setup is not very peppy.

adt tps, check compresson & do all needed work.

how many miles are on you car?
auto or manual?

PATDIESEL · Post by **PATDIESEL** » October 22nd, 2006, 11:25 pm

Kinda hard for the compression to be wrong. If it is then most likely the car wouldn't run. Most likely it needs a comrehensive tune-up. Change the air filter, fuel filter, plugs, wires, disty cap and rotor. Get a shop to do a navy soap cleaning on the motor (it cleans the combustion chambers, valves, intake). Then run some fuel system cleaner (use the instructions on the bottle, more is not better in this case). Use a good brand of synthetic 10w30 and keep up with the maintenance of the car to a T. Make sure any oil leaks are taken care of (replace the bad seal, don't use Stop Leak). Oil in the combustion chamber or anywhere else effects the performance of the car. The 1.8L is not all that fast and maybe he doesn't know the V6 is so small. Consider that most car companies make a four cylinder larger than 1.8Ls and the MX-3s power will make more sense. It is extremely smooth and built to be more like a Ferrari with its small pistons, high RPM and short stroke. (just 6 less cylinders and still even less than half the motor size).

hgallegos915 · Post by **hgallegos915** » October 23rd, 2006, 12:12 am

I second that.. a dyno should tell you if you are loosing power and you can get some a/f readings even if its not for race.

PATDIESEL · Post by **PATDIESEL** » October 23rd, 2006, 12:45 am

True, but I wouldn't waste the money on a dyno if you haven't done the suggested or it is time to do the above. 50-75 bucks on parts instead of a dyno should buy a good deal of what I told you to do.

666raCing · Post by **666raCing** » October 23rd, 2006, 3:10 pm

thanks to all who have replied. some additional information.

i have a 1992 MX3 GS with a standard transmission. i do not have any history on this car because im not the original owner. something's wrong though. im going to give it a tune up this weekend and report back if i see any changes.

thanks guys.

666raCing · Post by **666raCing** » October 24th, 2006, 9:32 pm

by the way, pat - my engine has 112k on it - will the navy soap do more bad than good to an engine with that much mileage?

PATDIESEL · Post by **PATDIESEL** » October 24th, 2006, 9:57 pm

Should be ok. Does it smoke, leak or burn oil now? If so how much oil is lost between oil changes? You can either measure the dipstick just before you cahnge it next time or measure the oil after you drain it. Better to just look at the stick before you drain it.
Navy Soap will clean off deposits and if you have a bad seal it will make it worse since the deposits will collect around the edges of a crack or tear in a seal and kinda clog it. However, you should replace bad seals and what as they come up. If you don't feel comfortable with having to replace a few seals then just do the tune-up and get some fuel system cleaner (use with regular gas. Some think premium gas will help with cleaning, but on a car meant for regular it is a waste of money and probably more harm than good since the motor isn't tuned for it) Then you can get some intake cleaner and clean what you can get to in the intake and throttle body. It will idle rough and run rough for a day or two after a Navy Soap cleaning or even with intake cleaner. It is the loose deposits being burned and thrown out.
You can also talk to the shop before you have it done to see what they think since they can actually see the motor and I cannot. Only shops can do a Navy Soap cleaning.

ven · Post by **ven** » October 25th, 2006, 12:37 pm

wht is a navy cleaning

and would a bad pcv valve or any other valve cause this mine does the same thing...

But it spits and spudders up to higher revs then it clears up only happen in lower revs or gears

i have done all the above wires rotor disty plugs checked for vacuum leak although not sure exactly what to spray with carb cleaner.

info for this guy would be great for me also.....

thx Im paying attention

PATDIESEL · Post by **PATDIESEL** » October 25th, 2006, 11:09 pm

Navy soap is a flamible liquid that cleans as it runs through the motor. It is injected in the intake, if I'm not mistaken, and runs all the way into the combustion chamber and is then burned and passed out with the exhaust. It is dangerous since it produces a ton of CO2 which can be dealdy. Trust me on this one. A buddy of mine is a mechanic and it sent him to the hospital from doing 2 cars in a row in a shop with tons of bay doors and all of them opened. The hospital said the CO2 attaches to the blood cells and won't let oxygen molecules attach and thus you will basically suffocate while being able to breath. (scary!)
A PVC valce can cause issues, but I've not heard of it causing sluggishness. A bad EGR valve could though. The online manual gives instructions on how to check the EGR valves and silinoids. I have never checked one so I cannot give any hints or info on it.