idle surging and vibrating, parts changed
 

hey guys i have a 97 mazda 626 i4, with automatic tranny, ok when i start my car it idles at 1000 rpms if i tap the gas pedal a few times it drops to about 500-600 rpm, but the engine vibrates alot, i had all the mounts changed except for the small one that connects the tranny to the cross-member under the car. i cleaned the iac, maf, throttle body. i tried to adjust the tps but could not get the readings that the manual specified, i adjusted the throttle stop screw, but could not get the proper reading and my idles still surges between 1000 rpms-and 500 rpms. i dont what the OEM adjust ment of this screw should be, if anyone can help with these issues i would be grateful. also is there and tranny filter for this model i hear on some sites "yes" and on others "no" Thanks

RE: idle surging and vibrating, parts changed
 

to me, it sounds like a MAP sensor issue. unplug the MAP sensor while it is running and see if it acts any different. if it does, replace the map

RE: idle surging and vibrating, parts changed
 

i checked and my car doesnt have a MAP sensor just a MaF, and i have cleaned the Maf sensor already, any other ideas?

RE: idle surging and vibrating, parts changed
 

i also changed plugs, wires, cap/rotor.

RE: idle surging and vibrating, parts changed
 

autozone is showing a map sensor for your car. it should have one.

RE: idle surging and vibrating, parts changed
 

Also, for the vibration issue, the tranny mount may be the most important one.
Since the engine is mounted laterally in the car, this mount is the one that takes most of the abuse. When you accelerate, torque from the engine pushes up on it. When you decelerate, it wants to pull it down. See what I mean?
I know I changed my OE mount to a harder AM one in my 3 and there was a huge difference. If yours is blown, it could have the same affect as installing a harder one.
BTW: After almost 2 yrs of trying to convince myself that I should love that mount,I finallyswitched back to the OE. MUCH smoother now.:D:D:D

RE: idle surging and vibrating, parts changed
 

i see what you mean, i had the mounts changed by the car dealer who i bought the car from, i can look and see that they are new mounts but how do i know if they are O.E? and what are the differences between them both and the only mount i didnt change was this little "L" shaped mount that connect the tranny to the cross-member i am attaching a photo of the mount i didnt change

here is the mount: http://www.yjdr.com/MOTORMOUNTS/PF07/A6440.JPG

i did take the mount that sits on top of the tranny off and felt the rubber it isnt cracked but the rubber is new and soft, should it be hard or stiff? do you also know what the measurement should be for the throttle stop screw, i mean what the clearance should be?

RE: idle surging and vibrating, parts changed
 

ok wsoape281 and guys i was wrong i found the map sensor in the back of my engine mounted to the firewall, i unplugged the sensor and nothing happened it didnt change at all.

RE: idle surging and vibrating, parts changed
 

sounds like a bad MAP then. check the bone yards for one since that one is pretty pricey new.

RE: idle surging and vibrating, parts changed
 

grrrr ok i will hit the pick n pull yard, also i unplugged the iac (since someone said to do so) and nothing happened to the engine either can that also be a bad iac? man i just got this iac about 2-3 months ago.