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i hope that this is a quick fix, and somone can help me.
i put in the poly urethane motor mounts in my car, and about three weeks later the car just feels like a dog, that is until you get to about 3000 rpm, then everything feels fine.
as i accelerate it almost sounds like the motor is skipping. could it be the tps? or the iac valve?
my car is a 88 2.8 mpi 5-speed that has been updated with speed density. could the update be the problem measuring air temp with the MAS?
another thing is i'm getting lower gas milage as i accelerate than i did before.
if any one knows anything please tell me.

MAS? You mean MAF (Mass Air Flow sensor)? If it has been updated with the speed density software then your MAF can be removed as the ECM now ignores it.

Is your computer spitting out any codes?

sorry, yeah thats what i meant. no the check engine light isn't comming on. i thought that you need the Mass Airflow sensor to measure the air temp, since i dont have a Incoming air temp sensor?

P.S. sorry i put this thread in the wrong section

I believe there is a manifold temperature sensor on your car also. I'm not sure about your problem though. Really it could be any number of things. It might be a good idea to try to extract some codes from the computer anyways. Do you know how to? Is the car idling fine? Does it miss at idle? during acceleration? Anything else you can tell us?

So you deleted the MAF and didn't install the IAT?

Ummmmmmmm  if this is correct....Press 1.

What Number do I Press if thats not the case?
i never said anything about deleting the MAF, what i said was that the car was updated and now uses the MAF sensor to measure Incoming air temp.
yeah, i does kinda sound like it's skipping, but i replaced the wires and plugs, so i don't think that the ignition could be the problem, but i could be wrong.
are you talking about the paperclip trick? my service engine light isn't comming on so would there be any codes to read?
and like i said before, i sound like it's missing when I accelerate.

"my car is a 88 2.8 mpi 5-speed that has been updated with speed density. could the update be the problem measuring air temp with the MAS? "
"i thought that you need the Mass Airflow sensor to measure the air temp, since i dont have a Incoming air temp sensor?"

Take out the MAF and install the Intake Air Temp senosr (IAT) .
Then see if it happens.


"What Number do I Press if thats not the case?"
For Habla Español press 2    

1988GTU, Is it required? I thought there was a manifold temp sensor in those MAF'ed cars already? I was reading an article on this speed density upgrade and it basically said the ECM will just ignore the MAF from then on. I can't see the shops installing an upgraded chip and then not putting a required temperature sensor on the car. But, then again, I suppose it's possible.

When I did the Density upgrade to my 88, it did not have the IAT.  It used the MAF. So I installed the IAT in place of the MAF.
I never tried running it with my MAF with the upgrade.

(1988GTU @ Jul. 11 2006,20:47)Q
U
O
T
EWhen I did the Density upgrade to my 88, it did not have the IAT.  It used the MAF. So I installed the IAT in place of the MAF.
I never tried running it with my MAF with the upgrade.
I'll have to pull out my book again. I could've swore I saw a manifold air temp (MAT) sensor in the 88-89 wiring diagram. Which, your right, is different than a IAT sensor.

So, scberetta3800, it might be worth swapping an IAT in its place.

A week before BerettaFest this year, i was messing with some stuff under my hood and had disconnected the battery. After which my idle was all messed up and was weak on low RPM performance, although not as bad as what you describe. A few days later I got a SES light for my IAT sensor. The wires got messed up so I fixed it and it runs perfectly again.

From what I can think for a 1988-89MPFI V6:
MAF
MAP 88 - IAT 89
IAC


IIRC:
TPS

ok, i got a IAT sensor (it is the one that is inside the air box right?) now i know that two of the wires from the MAF go to it, but what happens to the others? do you just leave them?
which wires do i use on the IAT?

You just cap off or heat shrink the unused wires.  Do a search for the upgrade.

um well i kinda figured out the problem... the valve spring failed on the intake of number 2 piston, it must have be getting awfull valve float and thus losing all compression on that piston.