Loss of power after radiator change

[Rickety]

I have just replaced a busted radiator on a 2000 Beetle 2.0L. The repair went smoothly... so I thought. About 20min into a test drive, I got the check engine light and a loss of power. It seems like it is in some type of safety mode. I have not run any diagnostics to find out any codes. Any ideas?

[Smileybug]

Codes would really be helpful.

[Rickety]

Copy that. I will update with the codes

[geniushanbiao]

Originally Posted by Rickety

I have just replaced a busted radiator on a 2000 Beetle 2.0L. The repair went smoothly... so I thought. About 20min into a test drive, I got the check engine light and a loss of power. It seems like it is in some type of safety mode. I have not run any diagnostics to find out any codes. Any ideas?

Pull the codes to see what's happening. It can be either engine or transmission. Transmission has limp mode while for engine it can be misfire or something else. Actually I don't think the radiator replacement and your power loss are related.

[Burke]

My forward O2 is dying, light on and loss of power. But not related to radiator swap. Check hoses and make sure you dont have a leak/tear from the work just performed.

[simonsi]

Originally Posted by Rickety

I have just replaced a busted radiator on a 2000 Beetle 2.0L. The repair went smoothly... so I thought. About 20min into a test drive, I got the check engine light and a loss of power. It seems like it is in some type of safety mode. I have not run any diagnostics to find out any codes. Any ideas?

Maybe as simple as some coolant dampened the coil pack??

Pulling the codes will point us all in the right direction...

[Rickety]

Any suggestions on getting it diagnosed? Would an auto parts store do it?

[simonsi]

Originally Posted by Rickety

Any suggestions on getting it diagnosed? Would an auto parts store do it?

Some in the US scan for free, try that, note the codes and post them here :-)

[geniushanbiao]

Originally Posted by Rickety

Any suggestions on getting it diagnosed? Would an auto parts store do it?

Autozone, advanceautoparts and some else can all scan and erase for free.

[Rickety]

Ok I finally got it diagnosed. Sorry for the wait. It seems as if the check engine light is a coincidence. When I first plugged in the diagnostic tool here is what I got:

P0422- Main catalyst below threshold

Then I got a list of “pending codes”:

P1128- Manufacture control fuel air metering
P0134- O2 sensor CKT no activity
P0301- Cylinder 1 misfire

I have noticed a rattle inside the catalytic converter. I thought it was a broken weld on the heat shield surrounding the cat. It seems this is not the case. I went ahead and cleared the codes with the reader and went out for another test run. The check engine light came back on but this time the diagnostic read a few other codes:

P0303- Cylinder 3 misfire
P0301- Cylinder 1 misfire
P0300- Random/multiple cylinder misfire detected

It seems the misfiring on the cylinders may have caused the cat to go bad? Am I on the right track? If so where do I start with trying to repair the misfiring? What exactly are “pending codes”?

[IndyTom]

It looks that one of your O2 Sensors is bad as well. If the cat is ratteling than yes it is Kaputt and needs to be replaced. The misfires probably caused the cat to go bad. Unburned fuel pools in the cat and melts the ceramic inside and cloggs the cat. It can cause engine damage if not changed. But before you do that you need to address the cause of the misfires. Check the coil, wires and plugs and more than like you will need to swap out one or both of the O2 sensors. Make sure you gap the plugs properly.

[Smileybug]

The 2.0 AEG cats are prone to failure (they issued an extended warranty on thats for just this engine to 10 years/120k even). The rattling of the cat is the internals falling apart. Its dead and needs to be replaced. Had this happen to mine too. No misfires though. Just a crappy part.

As far as the misfires, spark plugs, wires, ignition coil would be where I'd start.

[Rickety]

OK thank you guys for the information. I will make the repairs and let you know how I did.

[Rickety]

OK. I have replaced spark plugs, wires, ignition coil, and O2 sensor before the cat. After a test drive the check engine light remained on and the symptoms are still there. I ran the diagnostics again and another misfire on cylinder 2 occurred and a p1237. It seems as if it is not truly in a "limp mode". It will go to about 4000 RPM until it shifts, I just cannot get it to really down shift when I step on the gas. Any ideas?

[Rickety]

I have also noticed it seems to be using much more fuel than it has in the past while in this loss of power mode. Maybe twice as much as it should.

[IndyTom]

Did you gap the sparkplugs before installing them?

[Rickety]

Yes I did

[geniushanbiao]

Originally Posted by Rickety

OK. I have replaced spark plugs, wires, ignition coil, and O2 sensor before the cat. After a test drive the check engine light remained on and the symptoms are still there. I ran the diagnostics again and another misfire on cylinder 2 occurred and a p1237. It seems as if it is not truly in a "limp mode". It will go to about 4000 RPM until it shifts, I just cannot get it to really down shift when I step on the gas. Any ideas?

The late shift isprobably a TBA issue. Did you do the throttle body alignment?

P1237 points to the Cyl1 injector's electrical circuit. Check the resistance of your cyl1 injector and check the connector. The Cyl2 misfire can be caused by a bad cyl1 injector.

[geniushanbiao]

One possibility is that when you put the plugs back you forgot to plug back the cyl1 injector

[Rickety]

I do not recall removing the injectors. Is this something that i am just looking over? I will now look into the injectors. Thanks for all the ideas. I will get back to you with an update.