Pinging, now codes
Thread Starter
5th Gear
Joined: Sep 2005
Posts: 5
Likes: 0
Pinging, now codes
Have a 99 FRC. Live in the desert southwest so heat is a problem. For the last couple months (hot months) I consistantly get detonation under light to medium load (not WOT). Changed to 180 thermostat and adjusted fans. helped with the temp, but still get detonation but not as bad. Highest octane available is 91, and have added boosters with no luck.
Also found my first two codes ever, DTC P1220 & P1518. These appear to be related to the TP and Tac circuits. Could the pinging and codes be realted? Any ideas for a suggested cure? Thx, Fred in Yuma AZ
Also found my first two codes ever, DTC P1220 & P1518. These appear to be related to the TP and Tac circuits. Could the pinging and codes be realted? Any ideas for a suggested cure? Thx, Fred in Yuma AZ
Racer
Joined: Aug 2004
Posts: 401
Likes: 2
From: Allen TX
I also have a 99 FRC, and I'm having the same sort of problem. I live in the Dallas area, and the last couple months while it's been hot, I've been getting the pinging on light throttle. I use 93 octane Chevron or Shell. I noticed that it really shows up when my coolant temp gets over 200, which doesn't take long on a 100 degee day. There was another thread a few days ago about a knock sensor tech bulletin, but I'm not getting any error codes to indicate any sensor problem. I'm thinking of trying one of the top-end cleaner treatments to see if clearing out some of the carbon would help. My car has 35,000 miles. I never got any pinging until it was over 30,000. Anyone out here have any help for either of us???
Team Owner
Joined: Mar 2001
Posts: 21,325
Likes: 3,841
From: small town in S.E Pa. PA
St. Jude Donor '03-'04
Carbon build up can indeed cause increased compression, top end cleaner would help, a check on spark plug tips also. Running cooler will also help...a 160 stat with lower fan settings. a Larger capacity radiator... De Witt's or Be cool...
Instructor
Joined: Aug 2005
Posts: 133
Likes: 0
From: OKC OK
My car pinged bad here in OKC. Like Evil Twin suggests check your plugs. I was surprised that my car at 36,000 miles ran at all! The gap was huge, and the Platinum "pucks" were gone on every plug. They also looked like like the motor was running pretty lean...I removed my "Blackwing" and all is good. The plugs alone were good for a 95% ping reduction.
The carbon build-up (also suggested by ET) was also a problem for me. I used b-12 chemtool right before my oil change and it solved the other 5%. I generally run lower rpms on both highway and around town driving for the gas mileage and I think with the slower engine speeds, the carbon tends to build up faster. Perhaps a good, old-fashioned "redline tune-up" is what the doctor ordered(?)
However, I will say that if it is really hot, and I'm in too high a gear and low manifold pressure I can still get it to ping when I go WOT and lug the motor..but only for a second or two as the rpm's increase (obviously, running a motor like that would produce the expected ping)
R/
Dustin
The carbon build-up (also suggested by ET) was also a problem for me. I used b-12 chemtool right before my oil change and it solved the other 5%. I generally run lower rpms on both highway and around town driving for the gas mileage and I think with the slower engine speeds, the carbon tends to build up faster. Perhaps a good, old-fashioned "redline tune-up" is what the doctor ordered(?)
However, I will say that if it is really hot, and I'm in too high a gear and low manifold pressure I can still get it to ping when I go WOT and lug the motor..but only for a second or two as the rpm's increase (obviously, running a motor like that would produce the expected ping)
R/
Dustin
Racer
Joined: Aug 2004
Posts: 401
Likes: 2
From: Allen TX
konish,
Thanks for the info. I bought new Iridium plugs last week, but haven't put them in yet. I'll put in the plugs, and then try the top end cleaner if it's still pinging.
Evil-Twin,
Is there any other change needed to install a 160 thermostat? I don't want to cause the computer to throw any error codes.
Thanks to all for the help.
Thanks for the info. I bought new Iridium plugs last week, but haven't put them in yet. I'll put in the plugs, and then try the top end cleaner if it's still pinging.
Evil-Twin,
Is there any other change needed to install a 160 thermostat? I don't want to cause the computer to throw any error codes.
Thanks to all for the help.
Race Director
Joined: Jul 2005
Posts: 11,308
Likes: 1
From: The Beautiful Greater Bay Area California
Some great advice here. It is amazing how high summer temperatures bring out the "Ping". But, as ET suggested, decarbonizing, checking spark plugs, cooler thermostat (160)worked for me. 
Pro
Joined: Sep 2005
Posts: 693
Likes: 0
From: Gilbert AZ
Originally Posted by Red99FRC
I'll put in the plugs, and then try the top end cleaner if it's still pinging.
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Burning Brakes
Joined: Feb 2004
Posts: 1,136
Likes: 0
From: San Jose Ca
Originally Posted by Evil-Twin
Carbon build up can indeed cause increased compression, top end cleaner would help, a check on spark plug tips also. Running cooler will also help...a 160 stat with lower fan settings. a Larger capacity radiator... De Witt's or Be cool...
