should a bad Cat converter give a code??
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Cross-Country
Joined: Dec 2019
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should a bad Cat converter give a code??
Got a 2003 with the 4.2 and the engine began running shaky during acceleration and as I was taking off today I smelled the infamous rotten egg smell, the only code I and 2 different auto parts stores can get is the P1000 and nothing else, should my truck be throwing a code for the CC? also how can I tell which one of 2 is the bad one with no code, they both go into a single exhaust. One, which is the one I think it is when warm, the intake side (with a slight gold discoloration) is hotter than the exhaust side- is this a indicator its bad?? Thanks
Hotshot
Joined: Jan 2004
Posts: 19,762
Likes: 1,079
From: St Louis
should a bad Cat converter give a code??
The only thing monitored is the chemical activity of the upstream cats, nothing else is monitored by the PCM's software.
Fleet Mechanic
Joined: Jul 2019
Posts: 1,316
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If nothing else, I would pull spark plugs first and get a read on them before anything else.
My ‘03 with a 4.2 has a miss or something extra to the idle as of late. Took it to work for a drive a few Thursdays ago and it was fine. Friday morning, stumbly idle and turned right back home to trade out trucks. No misfires on the scanner, just the P1518 that had me stumped.
I’m expecting to find plugs that are oil fouled like I did five years ago, which probably means that some blowby is tripping that P1518 and I’ll need an engine sooner than later.
Anyway, enough of me thinking out loud. Pull plugs and diagnose first. Also, stop pulling battery cables and you won’t get P1000.
My ‘03 with a 4.2 has a miss or something extra to the idle as of late. Took it to work for a drive a few Thursdays ago and it was fine. Friday morning, stumbly idle and turned right back home to trade out trucks. No misfires on the scanner, just the P1518 that had me stumped.
I’m expecting to find plugs that are oil fouled like I did five years ago, which probably means that some blowby is tripping that P1518 and I’ll need an engine sooner than later.
Anyway, enough of me thinking out loud. Pull plugs and diagnose first. Also, stop pulling battery cables and you won’t get P1000.
More Turbo
Joined: Oct 2019
Posts: 632
Likes: 92
There is an easy way of telling if a cat is bad on one of these older trucks. (This will not work on newer type cats)
Go get the heat/laser beam type temperature reader from Harbor Freight (around $20.00) and get the cats hot, now aim it at the front and backsides of each cat, there are four of them. If the readings are close to 100 degrees from front to back on each cat they are bad. Anything over 110/120 degrees or more spilled is an okay cat.
Go get the heat/laser beam type temperature reader from Harbor Freight (around $20.00) and get the cats hot, now aim it at the front and backsides of each cat, there are four of them. If the readings are close to 100 degrees from front to back on each cat they are bad. Anything over 110/120 degrees or more spilled is an okay cat.
More Turbo
Joined: Mar 2003
Posts: 665
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From: Detroit suburb
But police officer, I was told to drive it this way because of my 02 sensor .....
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