Low RPMs

dreamx6 · 7-15-04, 13:38

There might already be a thread answering this question, however I thought this might be faster and return more up to date information:
I have a 1988 MX-6 GT (turbo) (STD Transmission) with 230,000 miles. I just put in a new AC compressor and dryer. I noticed that when I am approaching a red light, or stop and I let go of my accelerator, I noticed that the RPMs virtually go down to almost 200 revolutions. In about 2-3 seconds time it goes back to 750 (normal idling rpms). What is the cause of this? Injectors? ???

**Guy2626c** · 7-15-04, 14:02

check your throttle body boot. If it is still the stock one, it's LONG overdue for replacement. I had similar problems but with my atx. I've had the car stall when coming to a hard stop. Check this first, it's the simplist fix.

**DarkDragon** · 7-15-04, 22:55

its a vaccum leak of some sort, i would check the TB boot since its problly ur problem and is comon on our cars, other than that check any tube that holds vaccum such as IC piping, intake, and small misc. vac lines in engine compartment

dreamx6 · 7-19-04, 9:47

The throttle boot, is that the curved black plastic near the air flow meter?

Pardon my inexperience with the technical names, I am more a visual person.
Thanks for the quick response. In the meantime I will check any vacuum hoses for wear and tear.

**Guy2626c** · 7-19-04, 18:30

yes it is. For your GT it's the black plastic elbow near the vaf (afm).

dreamx6 · 7-23-04, 1:01

I checked it and it is on tight. I remember replacing that boot back in 1999. Still in good condition. Any other ideas? I also checked the vacuum hoses, and no leaks at all.

**Guy2626c** · 7-23-04, 11:12

you sure it doesn't have any tiny cracks in it. I would take it off and inspect it. Your problem sounds like a vac leak. It's not your injectors, you would notice other problems.

dreamx6 · 7-25-04, 0:22

I will double check the vacuum hoses and the boot.
I will let you know if I find anything. Thanks.

88TurboGt · 7-29-04, 23:14

i actually had that same problem tonight, but my car cutoff at a stop, my boot IS cracked, where can i get a new one?

SixSick6 · 7-29-04, 23:23

Mazda $83.03

**magik8** · 7-30-04, 0:15

For the GT, there is a boot on the throttle body, and a boot on the air flow meter. The one on the throttle body is the one that usually cracks.

88TurboGt · 7-30-04, 0:16

yep thats the one thats crack, stupid thing

**Jon** · 7-30-04, 0:18

It was only $60 from a Ford Dealer, you want one from a '89 Probe GT.

SixSick6 · 7-30-04, 0:40

I answered and posted the part number in your other thread

**DarkDragon** · 7-30-04, 11:29

just like every other part on our cars u can go to a junk yard and get a boot from another car but it wont last as long as a new one from a dealer but it will save u some money