P0300 sets on the freeway (with the typical flashing CEL) but if I only drive on the streets, No codes will set. The engine runs just fine, no surging or the "misfire feel"
On the streets, if I make a hard left turn the engine bogs or surges. not missing, but the same feeling as you would run out of gas. It not during the turn, it's slightly delayed. Lets say I make a left u-turn at 5-10 MPH, it surges as I straighten out, I try to accelerate, but it lags for 2 seconds. This does not happen on right turns.
It's possible the two symptoms are two separate problems.
I did the usual plugs, wires, and coil. Plugs are clean, no color on them. No leaking valve cover gasket. I tryied a .040 gap (Autozone specs) then read in the FAQ the gap may supposed to be .7-.8 MM which is .030 inch. No difference. I am going to open the tank up to see if the "sock" type filter is still on the fuel pump, but I am stumped. Any suggestions?
History of car...
This started out as a clogged cat, 1st cat disintegrated and pieces clogged the 2nd one. That is cleared out now. I had a dieing/no start issue that was a bad coil plug. CEL starts flashing (p0300) only on the freeway after 1.5 miles. One my "test drive loop" it always does it same time. CEL light goes off on the next start up, until I made a hard left turn, the car felt weak like almost out of gas. It set P1792 at that moment too. Once, but never since.
Post was edited for clarity.
Lanos P0300 on the highway
Moderators: daewoomofo, Moderators Group
re
hey your surging around corners sounds like you are getting air in your fuel take the pump out its underthe back seat and inspect all the rubber conections if you havent already mab just replace them anyways as they probably havent been done and make sure theres no dents in your tank.as for the code i dont know
Update, p0300 seems to set when coasting, or light throttle. Neutral and reving, back to Constant CEL. Also It will set the code in Park if Rpms are held at 2500 or above. The light flashes with steady throttle, light constantly on during deceleration. The light is always Constant when revving in park or neutral.
I found that placing a dime between the minimum screw and throttle, holds throttle just right to test the CEL. Quicker testing, and less gas. Unplugged sensors one at time, to see which limp mode fixes misfire.
No effect:
TPS
MAP
EGR
O2
No P0300:
CTS
IAT
MAP
Cam sensor (Used to detect misfire)
Did a test drive for CTS unplugged and another for IAT Both even temporary fixed the Uturn surge! I installed a IAT off known good car, P0300 back. Getting CTS to try tomorrow. Opening tank too.
All the tests, make this process of elimination long and painful... I am running out of ideas. Anyone else?
I found that placing a dime between the minimum screw and throttle, holds throttle just right to test the CEL. Quicker testing, and less gas. Unplugged sensors one at time, to see which limp mode fixes misfire.
No effect:
TPS
MAP
EGR
O2
No P0300:
CTS
IAT
MAP
Cam sensor (Used to detect misfire)
Did a test drive for CTS unplugged and another for IAT Both even temporary fixed the Uturn surge! I installed a IAT off known good car, P0300 back. Getting CTS to try tomorrow. Opening tank too.
All the tests, make this process of elimination long and painful... I am running out of ideas. Anyone else?