Ok, first of all I have a '98 Z28 convertible A4, that I just put a lid and MAF Ends on, the day before this happened.

I also just cut off my A/C compressor belt, as it was seized and no longer working.

Saturday I flew down to the Jersey Shore with no problems, hauling *** the whole way.

Then that night when leaving I had to step on a few obnoxious ricers that were messing with me.

I blew the rice away, but when one caught up to me at a light I slowed down to about 50 and manually put it in 2nd gear, and was punching, and revving it up a good bit, just to scare him, and make my nose jump up a little.

Never did I redline or hit the rev limiter.

But, after I stopped at the next light and put it back in drive, I heard a tapping noise at idle.

Then for the whole hour and a half drive home that tapping stayed, and has not gone away since.

It's not piston slap I don’t think, and it's not pinging.

It is a STEADY, consistent, light, but fairly audible, metallic tapping noise, that is coming from the top passenger side of the engine, and can be heard at all times or speeds.

Please help, I’m beat for a warranty, and this car is becoming a nightmare! <img border="0" title="" alt="[Mad]" src="gr_images/icons/mad.gif" />

 

someway or another it sounds like a bent pushrod or loose rocker arm...that would be the easy thing to check (puzzles me since you say you didn't hit the limiter) <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by BillyT:
<strong>Ok, first of all I have a '98 Z28 convertible A4, that I just put a lid and MAF Ends on, the day before this happened.

I also just cut off my A/C compressor belt, as it was seized and no longer working.

Saturday I flew down to the Jersey Shore with no problems, hauling *** the whole way.

Then that night when leaving I had to step on a few obnoxious ricers that were messing with me.

I blew the rice away, but when one caught up to me at a light I slowed down to about 50 and manually put it in 2nd gear, and was punching, and revving it up a good bit, just to scare him, and make my nose jump up a little.

Never did I redline or hit the rev limiter.

But, after I stopped at the next light and put it back in drive, I heard a tapping noise at idle.

Then for the whole hour and a half drive home that tapping stayed, and has not gone away since.

It's not piston slap I don’t think, and it's not pinging.

It is a STEADY, consistent, light, but fairly audible, metallic tapping noise, that is coming from the top passenger side of the engine, and can be heard at all times or speeds.

Please help, I’m beat for a warranty, and this car is becoming a nightmare! <img border="0" title="" alt="[Mad]" src="gr_images/icons/mad.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">on my 98 the injectors make a ticking sound off and on, but thats generally at startup for a few, then goes away after warmup

like fireball said, im puzzled since you didnt redline? But bent rods make that sound(generally you have to hit the limiter hard for that though)

 

1) What mods on the car?

Could be an exhaust leak.

 

Just MAF Ends and a Lid, and FRA

 

was it absolutely full of oil? if not and "sustained" high rpm ie..reving and jumping at rice....prolly a spun rod bearing. at least that what mine was after similar night. I was hoping for pushrod but no go. seems that these motrs espcially 98-99 starve for oil after hi revs.

sorry to bring the bad news. hopefully i'm wrong.

 

I thought bent pushrods was more of an M6 kind of thing, mines an auto.

Either way what would it cost to fix?

Could it also be a Burned valve or maybe just a lifter?

 

I had just topped the oil off that morning.

Although the car has the tapping sound it does not seem to have lost any power or smoothness at all.
In fact I'd say the car runs totally fine except for the tapping.
No hesitation, no skipping, or missing, no loss of power or bogging, no backfiring, and no roughness of idle or acceleration.
Just tap tap tap tap tap, like the way my old straight six used to do.

 

How many miles are on this car?

 

How much oil did it take?

Is your oil pressure gauge fluctuating?

If not, prolly not a spun bearing.

I would look for exhaust leaks and stuff like that. Might have a bad rocker arm.

 

It's not a louder 'knock' sound??

 

pull the valve covers and check for loose rockers/bent pushrods before you get all paranoid <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

 

Can you isolate the side?

Perhaps a messed up rocker arm or a bent push rod.

 

I heard the same noise after a harrd downshift and had 3 bent push rods. No fun at all. <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />

 

also check your plug wires, mighta shook one loose. look under your hood with the motor idling when it's dark out and see if one of your wires is arcing out. hopefully it's something simple. good luck.

 

It has 38,000 miles, and the oil stays normal, and its a rythmic metallic tapping, not really a knock sound.

<small>[ June 27, 2002, 12:58 PM: Message edited by: BillyT ]</small>