Ruff Idle Question.

[INFINITI Q45]

My Q45 has a ruff idle , it feels like a off balance vibration from the engine.The car has 128K on it and has been well maintained. How serious is this problem, and how can I fix it?

Thank you for any help.

[CrimsonQ]

year, service history?

[Rex]

My Q45 has a ruff idle , it feels like a off balance vibration from the engine.The car has 128K on it and has been well maintained. How serious is this problem, and how can I fix it?

Thank you for any help.

Not knowing any service history on the car, my first guesses would be either MAF (try cleaning) or injectors (ohm them to check). The process for both has been covered and can be found through some research and reading.

Welcome to NICO.

[Jeff Williams]

Rough idle can also be traced to a gunked up throttle body and idle air control passage. Be sure to clean this and the EGR as well.

I usually do this when I clean the MAF, and afterward I can't tell if the car is idling or not. I have to look closely at the tach so I don't try to restart the car.

Good luck and let us know what you find.

[gloucester Q]

jeff-any tips on how to clean the egr? -randy

[maxnix]

Ruff?

[elwesso]

jeff-any tips on how to clean the egr? -randy

best to take off the EGR valve andt he TB... Generally what gets gunked up is the port between the EGR valve and the plenum... Take the EGR valve off and seehow clogged it is... if its really clogged, you may have to pick at it with a sharp pointy object (screw driver)... Once you get all the hard stuff removed, you can use carb cleaner to get the rest.......

Some have even used a drill bit to get through all the carbon.

[goody90q45]

Will a plugged or malfunctioning EGR show a CEL code?

[elwesso]

it may..... IT can sometimes throw code 32...

[INFINITI Q45]

Thanks for response, its a 94. As far as I know it has been serviced, I have checked the oil a light tan color, I looked at the MAF it looked clean, the air filter has just been changed. I will clean them any ways. EGR, MAF,& throttle body. I hope cleaning will fix it.Again thank you all for the help.

[[email protected]]

if you still have a problem after you check some of the things listed , the next step i would say is to change the injectors . one of them could be stuck open (dumping to much fuel) this is a common problem, alot of cars never see the correct repairsin this case .. let me know how you make out ,,

[Q45tech]

"one of them could be stuck open (dumping to much fuel) this is a common problem, alot of cars never see the correct repairsin this case .. let me know how you make out ,, "

Never in my life have I seen a struck open Q45 injector! Or even heard of one from a reliable source. The failure mode is not opening or mechanically clogged/restricted or slow opening.

I have seen one or two shorted ecu or injection harnesses that resulted in a forced open injector [usally after a severe accident].

[blondi]

i bought a 1990 Q45 a year ago. i had a used motor put in. this is my first time ever driving the car so im not sure how the feel of the car is supposed to be. the motor runs loud. and very rough. i know nothing about cars so i am just curious on what would cause a motor to run so loud. also my heater is not working. if you put your hand on the vent you can feel it is warm but it is not blowing any heat. what could that be. i am clueless on how this web page works if someone could email me with any suggestions i would appreciate it. [email protected] thank you

[Q45tech]

"i am clueless on how this web page works"

Perhaps you are clueless? Normally one spends around 100 hours researching and reading a few thousands posts OR signs up for community college/votech and takes a degree in automotive technology to understand basics applicable to all vehicles.

We have high standards here and expect members to do their part instead of being spoon fed every minute detail.

[paranoidjack]

"i am clueless on how this web page works"

Perhaps you are clueless? Normally one spends around 100 hours researching and reading a few thousands posts OR signs up for community college/votech and takes a degree in automotive technology to understand basics applicable to all vehicles.

We have high standards here and expect members to do their part instead of being spoon fed every minute detail.

Should that prove too challenging or not manageable for one reason or another, at least start another topic (Off topic conversation muddies information and makes searching difficult).

[TheJerseydude]

I am having a rough idling issues also. When i first got my 94 Q in 2006 I couldnt even tell whether or not it was running most of the time! now I cant stand idling at drive thru windows lol. Can you give the "for dummies" version of where the EGR and MAF are and how to clean the throttle body?? Thanks in advance