P0401 issue :(, Somebody has fixed this problem?? Options

[rapidfire]

I saw a lot of posts about the p0401 code, but i can´t find somebody wich fix this code. i already did all this changes to my car.

i changed the next list:
spark plugs wires
spark plugs
distributor cap and rotor
head gasket
fuel pump
fuel filter.
MAP sensor

cleaned:
EGR valve
IAC valve
checked all egr vacumm lines

and i have same problem, same p0401 code, my car its on very slow rpms it shakes on any speed (10, 30, 60 MPH) and i have no idea what else to check to fix this problem ... did someone else having this problem and got fixed??

thank you!!

[ILoveMySilly97]

I'd start with mild stuff like run premium gas AKA 91 for NA or run 93 for turbod. I'd recommend running on high quality gas. I run 89octance Chevron gas in my lil 5sfe daily. Run like that for a week and see if there's any difference. If not then use Lucas Fuel Treatment or the Sea Foam.

[ILoveMySilly97]

Btw, you meant the engine would shake like as in it would stutter like its about to stall?

[Box]

It's an EGR code, which means it'll be one of four things: EGR valve, EGR modulator, EGR solenoid, or EGR temperature sensor. The solenoid and temp sensor can be tested with a multi-meter. When you cleaned the EGR valve did you also clean the tube? Usually the tube will get clogged up causing the problem.

Here's how to test for the 7A-FE, it's close enough to the 5S to give you a better idea on what to do though: http://ww2.justanswer.com/uploads/skyvisio...44_95_rolla.pdf

[rapidfire]

Btw, you meant the engine would shake like as in it would stutter like its about to stall?

That´s right .. some times in stop light the car just stalls..

[rapidfire]

It's an EGR code, which means it'll be one of four things: EGR valve, EGR modulator, EGR solenoid, or EGR temperature sensor. The solenoid and temp sensor can be tested with a multi-meter. When you cleaned the EGR valve did you also clean the tube? Usually the tube will get clogged up causing the problem.

Here's how to test for the 7A-FE, it's close enough to the 5S to give you a better idea on what to do though: http://ww2.justanswer.com/uploads/skyvisio...44_95_rolla.pdf

i had cleanded the tube but with the valve out of engine. let me check this link. thank you a lot guys!

[Bitter]

Usually the modulator has failed, the diaphragm inside is torn and the modulator must be replaced.

[Box]

Usually the modulator has failed, the diaphragm inside is torn and the modulator must be replaced.

That, what ended up happening to mine after running through all of the tests.