Hello.

Thanks, in advance, for any constructive advice on my Camaro 4th gen. 1993 v6.

Here it is:

now the car vibrates at idle only; the transmission shop said the old transmission mount might have domino effected the motor mount(s) and messed them up.
I'm wondering if he is passing the buck, but his shop is highly reputable so I don't want to upset him or be too pushy. He highly suggested, I take it to a trusted general mechanic.

So I either have 1 or more bad motor mounts that I have to take to the general mechanic who did a good job at a reasonable price since the engine has to be hauled out High to get to the oil pan gasket in these Camaros. I'm glad I don't have to check the oil as often even though the leaks were minor.

Now I'm wondering how long I can drive with a car that vibrates on idle so that you can feel your feet on the brake vibrate, too. I've heard people drive for years on a bad motor mount(s), I guess that's Ok if you don't slam on the gas and go racing since that would shake the motor mount etc.

I'm tapped out. There are 2 main reasons for a Vibration @ idle: 1) Bad motor mounts 2) Fuel Injection system is dirty (the 2nd one seems like a much cheaper fix) Now I have to save for a motor mount replacement or option 2: the carbeurator and fuel injection system may be dirty, etc. Hopefully, it's a cheap fix. Motor mounts even Original Manufuctered ones are inexpensive delivered let's say by Napa Autoparts. Then labor this general mechanic-dude charges $80 an hour with a free diagnostic. So I'm guessing with parts and labor I'm looking at $200 or $250 (which includes labor) versus what he charged me for a 3 hour oil leak fix job of $450. *I bet a motor mount exchange can be done in 1 hour, or 1 and a half hour tops. By the way, the general mechanic couldn't give me an estimate since he needs to know the # of motor mounts affected.

I'm thinking $250 to replace motor mounts includes labor
$150 to clean fuel injection system

any thoughts?

car vibrating at idle is not a good feeling. Thanks

This general mechanic who did great work on my oil leak repair was chill enough to say that I could call him after the holidays so I guess I can drive it for a long time until I save enough money.

 

You have touched on about 1% of the things that can cause a vibration at idle and the motor mount is highly unlikely.

Dirty IAC
Leaking or dirty EGR valve
Dirt in an injector
High resistance in the plug wires
Worn or dirty plugs
A small single cylinder vacuum leak
O2 sensor not reporting the correct exhaust gas
Carbon build up on your valves
Dirty or failing air temp sensor
A blown head gasket....

I am sure I am forgetting a bunch of stuff, the reason I did not mention motor mount is because they do not normally present as a vibration. A good running motor will idle sitting on its oil pan on the shop floor and not vibrate. Normally when a customer comes in with a broken motor mount the complaint is a clunking noise when they put it in gear. I am not saying it is not possible that motor mount can cause a vibration but I am saying if the motor is running right it would be very tuff to detect a bad motor mount based on a vibration as idle. The test for the motor is to power brake the car while someone watches the motor or just use a pry bar.

First try some fuel injection cleaner and a tank of the good gas Higher octane fuel like the Exxon 93. Also run the car up at a little higher RPMs then normal going down the road a few time.

 

I already added the normal dose of fuel injector cleaner and that guaranteed to smog cleaner. I didn't go overboard. In fact, only 2 days ago, I passed Smog. Before the smog guy got real close to it. I was still experiencing this vibration. However, when my driveshaft did not connect, I did really push the accelerator to 55 mph. I am hoping that did not damage the head gasket or piston? (now u got me worried)

 

i think the trans. shop dirtied something or the old transmission mount damaged the motor mount.

it happened immediately right after I left there and they installed a new drive shaft

in fact they test drove my car they shoudlv e said hey at idle ur car vibratess unless they thought I knew this already?

my car was given a full tune up 8 months ago.

It may need EGR valves good point

All vacs are sealed and in shape.

 

Mechanic fix the complaint on the work order, it is up to the service adviser or shop foreman to communicate other issues to you.



What is a full tune up seems to depend on the shop. In some shops that just plugs\wires\fuel filter\air filter.

Unless you have done and enrichment test on this motor since the vibration started there is NO WAY you could know that. Micro Vacuum leaks in intake gaskets are very common on cars older then 12 years. I knew one mechanic that would not even try to fix a idle issue on a car unless he did a new intake gasket. I don't 100% agree with that but I could not argue with the fact that every car that he did do idled like new.

Notice I said dirty EGR valve not bad EGR valve. It could be bad but there could just be dirt keeping from sealing. If the port is gummed up and you put a new valve in the it will just get dirty in a month or two.

Dirty EGR valve is number two on my list. That list is in order of the most common issues. If I was working on a car with a recent tuneup and a bad idle I would go right for the IAC and I would re-torque the intake bolts first thing. In fact I considered that part of the tune up but most shops do not.

 

Hi, Gorn yesterday my general mechanic went under the hood for a diagnosis of this and saw the vac, tubes etc., sprayed something, lowered the idle. I've copied and pasted it here. It's interesting:

thanks that is very good advice. going to a better shop than the one I went to after the holidays for an "indepth" thorough diagnosis that actually looks under my chassis. Again: general mechanic to actually pull up and look under the chassis. I went yesterday and the general mechanic who sealed my oil leak for about $425, added some type of spray under the hood and lowered the idle. It doesn't happen all the time at a stoplight or traffic light. and not a thunderous vibration. I was told yesterday that all motor mounts are there and are just old. I might have to replace them.

Anyway, was not impressed that they didn't prop my car up and look under it. I know they're probably busy like everyone else is this time of year, and they didn't charge me for all their "diagnosis" yesterday, but I want a permanent fix. I will take it to either of 2 of the best mechanics here to make it smooth at idle All of the time after they diagnosis it.

*If an oil leak repair on my 93 Camaro was $440 this is a $250 including labor job and I'd even pay a tad more for a permanent fix but they'd really didn't spend too much time on a diagnosis. I think if you pay for something, it's indicative of better quality. (I knoww there are exceptions, but this is usually how it works).

Thanks, again. Have a happy New Year

in other words, the problem is still there after the general mechanic added spray under the hood to the engine and lowered the Idle; per the mechanic doing the diagnosis: all motor mounts are there, but just old. a new transmission mount adds more power to the engine so I would expect there's a need to replace the old motor mounts to handle the added power. After I left the general-mechanic shop, it still had the problem but not all the time. These guys are a bit younger working on my car, I'm taking it to some less lax mechanics who are older and wiser, like there was his neighbor next door who was working on a '65 Mustang. I called him up and he said he has no qualms dealing with his business neighbor (me) and that it's not unethical.