Fierokyle

Hi all, I recently bought a 04 ls430. I love the car so far, but after I replaced the spark plugs It seems like I have to give it far more gas before it will accelerate. It’s possible that is just in my head because I wasn’t very used to the car prior to doing this but I noticed a difference on the first ride after. I forgot to plug one coil in and when I started it had a misfire for a second before I plugged it back in. Is it possible that just screwed with my ecu settings and I just need to reset it? Thanks all.
no cel, spark plugs are ngk ifr6t11, and when I floor it the car seems to downshift and accelerate fine, but something like 75% throttle doesn’t seem to do much

JZZFZZ

I would disconnect the battery and try again. If that does not work, I would check the plugs. Are the plugs legit? Heard too much about counterfeit lately.

Fierokyle

The plugs should be legit, I purchased from rock auto and they were listed as oem.

911LE

Clean your MAF and throttle body.

Fierokyle

definitely planing on it hopefully sooner than later, also have some fuel additive I’m gonna try when I get down to a half a tank.

BigBoomer

Running it with one coil not connected will have thrown an error code and set the ECU into limp-home mode.
Disconnect the battery, wait 15-20 mins, then reconnect the battery (resets limp-home mode) and immediately go for at least a 20 mile drive on a variety of road types so that the ECU can learn your driving style.
I recommend flooring it at least 2-3 times during that drive.
After the battery disconnection it should drive fairly normally, but that last little bit comes from the learning of your driving style.

jimisbell

mine was sluggish till I pulled the 3rd CAT and found it was totally plugged, was surprised it even ran.

lp2k

Check the gap on those spark plugs. Book says 0.043

texan_176

iTrader: (5)

Have the battery tested. Just because it starts the car every time does not mean it is healthy. Years ago my car would accelerate from a stop like it was down 30% on power. The transmission was also very lazy and slow to change gears. I went crazy trying to figure this out. My mechanic of 30+ years experience nailed it and a new battery immediately fixed the problem. If the power draw is low or unstable from the reservoir of energy, the electronics all go bonkers.