Cadillac Owners Forum banner

1 - 14 of 14 Posts

·
Registered
2002 Deville
Joined
·
52 Posts
Discussion Starter #1
I've got a 2002 Base deville. I've got this strange ticking noise that seems to come from the drivers side dash area. I'll try to describe the symptoms as best as possible.

I can't hear anything with the hood open that's out of the ordinary. I can only hear it with the windows closed. It ticks the worst when the car is under load. You can barely hear anything if the car is parked and reved, or when the car is rolling and I put it in neutral and rev the motor. It get louder with the engine rpm in gear. The car is not throwing any codes.

It has been going on for a while. In the meantime I have replaced the following which had no effect on the ticking noise. Front motor mount, plugs, ignition boots, air filter, and fresh oil change. The car runs great besides this little noise that is driving me crazy.

Please help me regain my sanity.....
 

·
Administrator
2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
Joined
·
68,480 Posts
Remove and clean the EGR and ports. Low EGR flow at low to medium speeds/loads will cause a perceptible spark knock. (NO, you won't fix it with 93 octane gasoline - clean the EGR system. Tutorials down in Cadillac Tech Tips.

OR - a loose or failed exhaust manifold gasket or head pipe-to-cat flex joint gasket. Exhaust leak.
 

·
Registered
2002 Deville
Joined
·
52 Posts
Discussion Starter #3
Thanks Sub, I'll definitely clean the EGR as the car just rolled 100k and I'm pretty sure it's never been done. At least not as long as I've owned the car. Would the low EGR flow cause a check engine light or code?

It's not an exhaust leak as it can't be heard outside the car.
 

·
Super Moderator
White Diamond '03 DHS (with DTS floor shift)
Joined
·
86,785 Posts
Yes, the EGR valve is monitored and will trip the SES light and set a DTC if it is not functioning properly.

Here's a few examples.

P0400 - Exhaust Gas Recirculation Flow Malfunction
P0401 - Exhaust Gas Recirculation (EGR) Flow Insufficient
P0402 - Exhaust Gas Recirculation Flow Excessive Detected
P0403 - Exhaust Gas Recirculation (EGR) Solenoid Control Circuit
P0404 - Exhaust Gas Recirculation (EGR) Open Position Performance
P0405 - Exhaust Gas Recirculation (EGR) Position Sensor Circuit Low Voltage
 

·
Registered
2002 Deville
Joined
·
52 Posts
Discussion Starter #5
Just went out and double checked. No codes are being set for the EGR. The crazy part is I can't hear the noise while standing over the engine with the hood open, but can hear it in the car with the door and windows closed. The noise sounds very similar to when a cable was going bad on an old cable driven tach or speedo. The EGR looks pretty easy to get to, especially after doing the plugs today. I'll clean it first thing tomorrow and update the thread. Thanks again guys.
 

·
Administrator
2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
Joined
·
68,480 Posts
Can't hear it outside the cabin ?? Under load only....... start looking for an exhaust system leak or "grounding" - a part rattling against the body. Steering rack or intermediate steering shaft. How about the aspirator - the tiny computer fan for the air temp sensor in the tunnel behind the grille just left of the steering column ?
 

·
Registered
2002 Deville
Joined
·
52 Posts
Discussion Starter #7
Sub, the aspirator? Is it in the interior? How do I get to it? Any pictures? The ticking sounds like something that could come from a computer fan
 

·
Administrator
2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
Joined
·
68,480 Posts
OK - Look just left of the steering column - a small 1" square grille. Stick an ear down next to it - that grille is the opening to a tunnel tant leads into the dash to the aspirator module - a thermistor/circuit board/muffin fan that senses interior air temperature and uses that to modulate HVAC temperature door movement. The fan sleeve bearing dries out after XX years and needs to be lubricated. In the Seville body you yank the end of the dash off, remove the plastic window vent duct and the small hex head s/m screw straight in. Fish out the wiring connector and the module. Open the fan hub and lube it with a drop of synthetic engine oil, replace the hub seal, and put it all back together.

Some time ago, iametarq posted a tutorial with pictures - Google "cadillac forums deville hvac aspirator fan repair" or something close.
 

·
Registered
2002 Deville
Joined
·
52 Posts
Discussion Starter #9
Just found and cleaned out the aspirator fan. It's on the right side of the steering wheel on the deville. Was a little dusty but working fine. It's not the cause of the ticking. I'm giving up for tonight, first thing tomorrow, the plan is to clean out the EGR, and while I'm in there I'm going to clean the IAC and TB just for good measure. Thanks for all the help. I'll keep you guys updated.
 

·
Registered
2011 Crown Vic LX, 2009 Chevy Malibu 2LT
Joined
·
5,607 Posts
if this only happens when the engine is under load, concur with sub that this is likely an exhaust leak. I wouldn't go too crazy snooping around the HVAC
 

·
Registered
2002 Deville
Joined
·
52 Posts
Discussion Starter #12
This morning I cleaned the EGR, throttle body, and IAC. The noise is still there. Guess I'll throw it up on a rack and look for exhaust leaks. The crazy part is I can't hear the ticking noise outside the car. Only on the inside. I'll check the cabin filter, but it was replaced this year.
 

·
Registered
2002 Deville
Joined
·
52 Posts
Discussion Starter #13
I think I've found the leak. It's coming from the rear manifold, Around the area where the egr pipe fits into it. Doesn't appear to be coming from the joint. It appears to have developed a crack. The mechanic told me the manifold will need to either be replaced or taken out and welded. The big question is can the rear manifold be replaced with the motor in the car?
 

·
Super Moderator
White Diamond '03 DHS (with DTS floor shift)
Joined
·
86,785 Posts
Since guys have done HG replacements with the engine in the car, I'm sure it can, but probably won't be real easy.
 
1 - 14 of 14 Posts
Top