Buzzing sound from under the UIM
 

i posted a few days ao how y car wasnt starting. several members suggested changing the spark plugs and making sure it wasn't flooded. i did that and its still not starting. i tried to push start it wth some friends and that ddint work. some white smoke did come out of the muffler after we tried push starting it and when i try to start it with a key.
does anyone have a clue as to what it might be? the buzzing is coming from under the UIM. sounds like its from the fuel pressure regulator. any other suggestions would be appreciated. thanks

you might want to check to see if you have fuel pressure. Your fuel pump might be gone. Do you remember ever getting any stuttering or little lags in acceleration before you had this problem?

it wouldn't have anything to do with your problem but a stuck/bad ISC can make a buzzing and its under the UIM

ive never had a stuttering problem with my car before it happened. i got a feeling its my ignition. i think i might have to give in and bring it to lowe's automotive on monday. mikes a good guy there.

You're in the same boat as me...alot of people seem to be having this problem randomly. The buzzing I'm almost positive is the ISC, unplug the white plug under the UIM to see is the buzzing stops. It might be the fuel pump...I'm actually waiting on my new fuel pump to come in, so I can't tell you if that is the cause of my problem yet. If you figure out the problem please post up.

That buzzing may be the fuel injectors. If it's coming from under the UIM it obviously isn't the fuel pump. The only times I've ever heard it in the past 8 years (in both instances the car wouldn't start and the buzzing happened after cranking):

(1) When my battery was almost dead and I flooded the car trying to start it.

(2) When my fuel feed and return were swapped, so the injectors weren't getting any fuel.

My car runs fine, if it dies for some reason other than the key being turned to off than there will be a buzzing from the UIM area. No doubt it is the ISC (atleast on my car, double check on your's by unplugging it), and as far as I know mine still works. I believe the buzzing is just the solenoid cycling real fast. I would look elsewhere for your problem.

Thread resurrection.


Any other situation that you've seen besides that?


Symptom: Cranks strongly but doesn't start.

Facts:
Car worked fine a few days ago when I drove it.
Battery is fine and shows good voltage.
Fuel feed and return haven't been touched.
Fuel gauges shows that car has gas.
CAS looks good.
TPS settings are good.
Wires and hoses at the fuel tank look OK.
Ignitor is connected.
PFC seems fine.
No oddities in the Sensor check on the commander.



After I stop cranking and leave key in ON position, I hear a LOUD buzzing sound from under UIM. I also feel the buzzing when I touch the UIM. It feels and sounds like its coming from closer to the LIM so I don't think its the coils.

I don't think I smell any fuel so I don't think that I've flooded it yet. I've tried starting it by cranking 5-6 times for about 15-30 seconds at a time.

FSM hasn't been much help with this at all.

Help would be appreciated.

gracer7-rx7, try disconnecting the ISC and see if the buzzing still continues.

And although the CAS looks good,check the plug for moisture.This happened to me and was wihout a car for a week before pinpointing it to the CAS.Good luck

Bingo, that's your buzzing.

Might not be a bad idea to remove the ISC from the back of the UIM and clean it thoroughly with carb cleaner to loosen it up. If it is indeed bad, I can always send you one Alberto, I must have a dozen of them laying around :)

Thanks. I'll try the ISC tomorrow but the sound doesn't sound like its coming from there. I couldn't get my hands on the plug earlier.

i gotta ask, whats the ISC

what does isc stand for?:scratch:

Idle Speed Control Solenoid, located on the middle rear of the UIM. If it fails the car will not hold an idle until you manually adjust all the TB screws.

I ran without one for about a year and hated it, the car runs much smoother with the ISC.

does the block off plates eliminate the isc?

Block-off plates don't eliminate anything on their own. ;) There is a block-off plate for the ISC *IF* you choose to remove it.

Will failing Idle Speed Control selenoid can cause surging idle?

Potentially but most of the time surging or hunting idle is caused by throttle body mechanical settings being out of adjustment. There is a thread in the Archives about adjusting that and link in the FAQ thread stickied in this forum. The FSM also has the steps to adjust these.

But I believe his problem is cranking and not starting,then hearing the buzz which happened to me due to the CAS being faulty at the wires.IMO,he should check that too