Engine Knock???????

[ICEMAN007]

Hey everyone, I am extremely puzzled by what took place today. Ok, my car is a 1993 MTX with 155K on her. Never any engine ticking or knocking of any sort, ever. I just recently purhased this car and am in the process of doing the 60K very soon since I have no idea what has been done by the previous owner(s) so better safe then sorry.

So this morning I went over to a SHO Club Member Joe's, aka whiteman 01, house to just simply remove the intake and do new plugs and wires. So we pulled off the intake and also did the coolant bypass from the throttle body. He also gave me his C&L 73mm MAF to see if it would work out with my car. And then shortly after that, I went and and purchased a new pre oiled K&N air filter and threw that in.

Now check this out! Here is what happened after driving the car to run some errands around the cities. So I would say my fiance and I were driving for about a hour or so on the highway before pulling into TGI Fridays for dinner. As I pulled into the parking lot I noticed a scary sound coming from my engine. It was knocking. Not real bad but loud enough to make me wet my pants. (didn't happen but almost! ) And not a ticking or pinging sound, it was engine knock. I thought I maybe I was just hearing something so I slowly pushed down the gas pedal and the knocking got louder. I parked the car to check the vitals. Engine was at normal temperature, oil and coolant levels were right where they should be and there were no obvious leaks of any kind from underneath. So we went into eat, well I didn't eat since I was absolutely sick to my stomach. My fiance and I were in there for about a half hour or so before leaving back to the house only a mile away. I started the car back up and the knock was still present. So I gingerly drove the car out of the parking lot, keeping the RPM's to the absolute lowest point as the knocking was still present. When I got to the stop light about three blocks away I noticed the knocking sound had magically gone away. I wasn't sure so I slowly upped the RPM's and still no knock! So I once again gave it gas, this time really stepping on it and still nothing!!! The rest of the way home no engine knock and no decrease in power. I parked her in the garage and turned the car on and off a half a dozen times, revving it up aggresively and every time, no knocking from the engine!!!

Can anyone PLEASE tell me what the heLLLL has happened here????? Could the C&L 73mm MAF cause an engine to knock? I did a search and found nothing as to engine knock due to a C&L 73mm MAF. And how can a engine knock and then just go away? I thought once you heard knocking, your pretty much screwed! I checked to see what codes came up and the only two I'm getting are a code 147 and a code 219. ANY IDEAS, THOUGHTS, OPINIONS, SUGGESTIONS WOULD BE GREATLY APPRECIATED!!!! I hope to hear back from a lot of you. -Cope

 

[Kens1992mtxSHO]

First off ditch the C&L MAF. You're better off with the stock MAF unless you've had some programming done to your SHO for this modification. Code 147 is a TPS problem, but could be related to the C&L you've got.

Second-

Service Code 219 indicates the spark timing has defaulted to 10 degrees BTDC. The SPOUT signal has a variable duty cycle with amplitude that varies from 0.4 volts to VBAT. In the event of a SPOUT failure, the DIS module will generate a fixed dwell and constant spark angle based on CID and PIP signals (FMEM mode).

Possible causes:

-- Damaged DIS module.

-- Damaged SPOUT circuit.

Do this:

-- Key off.

-- Disconnect processor 60 pin connector. Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.

-- If you have a BOB, install it on the PCM connector, leave PCM disconnected.

-- Disconnect DIS module (pins 1-6).

-- Measure resistance between Test Pin 36 at the BOB and SPOUT circuit at the DIS module vehicle harness connector.

....thanks Bizzy for this info

This info is stuff I found just by searching for it on the forum. It's out there...

 

[SuperHO]

What the ****, man! He was wondering about his knock.....



If I were you, I'd tear the bottom of the engine off and change the rod bearings, just for preventive maintenence. My old 92 started doing that at low RPMs under load, so i changed em, and that engine currently resides in my 95 and is still kickin.

 

[RStalveyARFF]

Yes, and there's a reason code 219 is being displayed. The engine doesn't revert back to base timing tables often... Either A, the knock sensor heard the noise and pulled back all the timing, or B, it was something else. He never said anything about an oil light flicker so I'm curious.

 

[FamilySHO]

In my car the knock would appear under load (going up a slight hill in 5th) at 2300 to 3200 rpm. It would not appear if you simply reved the engine in the driveway. Don't know if this is typical.

 

[SHOtime2511]

where on the engine is the knock coming from?