Hey guys,

Starting today, when I start my car, it makes a kind of vibration. Only when it starts, it kind of rumbles. Does not make a really loud noise, but it kind of knocks and vibrates. How serious is this? What could this possibly be? Am I safe to keep driving this?

I think that my brother and I have narrowed it down to a problem with the intake and motor. It is almost like it is running too lean and not supplying enough fuel to the motor when it starts up. Is there anything else that could be a problem? Also, when I start moving from first, if I do not give it a lot of guess, it does the same kind of vibration, without the noise..

Does anyone else have this problem? Any fix ideas? I am thinking about just taking off the short ram and putting the stock air box back on..

 

bad compression, rod knock, do a compression test and a leakdown if the compression test turns up good.

 

Oil is up to spec? Have you checked it for any debris?

Motor mounts aren't torn or otherwise bad?

Is your car an automatic, or a manual?

Has the MIL (aka check engine light) come on? Have you checked for stored codes anyway? (sometimes the ECU will store codes without the light coming on)

How many miles are on the car?

Have you done any recent maintenance to it?

 

Yeah, motor is debris free.
Motor mounts seem to be fine.
Manual.
CEL came on the other day when I installed my intake, but that is only because I left my afcv (air flow control valve) off for a drive to autozone 2 blocks away.
Recent maintenance; Oil change yesterday and than installed the intake on Saturday
I think that the motor is just running a little lean on the start. You know when you shift up to too high of a gear and get a little bit of a rumble? I think that is the most appropriate comparison of what it could be

 

Throttle cable or throttle plate sticking? Sounds like you may have a vacuum leak if it's running lean.

 

Found out what was going on. Thanks for the suggestions.

 

Well, what was it?

 

The *********** at Jiffy Lube loosened the intake pipe bracing.

 

Number one reason why I've done my own oil changes for the last 20 years.

 

Haha true that.

 

Yeah, I am going to from now on. They usually have been nice and fair. Always even give me a discount because I know the managers daughter. But, one of the tech's was telling me that my Radiator cap was bad last oil change, didn't change it and than called him out on it this time when he was telling me other stuff that was "bad". That it why I am thinking that they loosened it.

 

You sound pretty pissed for having such a small/insignificant mistake being made.

 

No kidding.

Change your own oil.

 

Sorry that I don't like it when people mess with my motor/performance/money.

 

Sorry bro, that's just life. For everything you have there is someone out there who wants it. Lessons learned are expensive sometimes, just be thankful this was a cheap fix.

 

Yeah, and I am very thankful that they did not do permanent damage and it was an easy fix. I just hate that there are people out there that would want to **** up other peoples work/money. It did not cost much, took like 12 minutes to remove my air box and install this intake. But still, that could in the long run cause some potential damage.