System to lean bank-1 - 2003 Jaguar Vanden Plas

SOURCE: what does engine fault code po171 system too lean bank 1 mean thanks

i think its the oxygen sensor (pre cat) in exhaust

SOURCE: PO171 error code System too lean bank 1

Here are some possible causes, I would start with anything related to replacing the intake.

Air leaks in intake manifold, exhaust pipes or exhaust manifold
Fuel control sensor is out of calibration
Low fuel pressure (fuel filter clogged, pressure regulator failure)
One or more injectors restricted or pressure regulator has failed
O2 sensors contaminated, deteriorated or has failed
Vacuum hose is disconnected, broken, leaking or loose

Dave C

• 1050 Answers
• Posted on Mar 26, 2009

SOURCE: vehicle failed emissions testing

You need to replace the intake upper plenum gaskets. There is two pieces, a top cover with one big silicone o-ring gasket and a lower half with six smaller silicone o-rings for the individual intake ports. You can buy these as a set, just for this job. Start this job by removing the wiper blades, then release all the screws, (including the ones that support the wiper motor), that hold that big black plastic valence at the back of the engine compartment. Pull that out of the way, you will have to pull the windshield washer hose through it, just disconnect it on the engine side, now you have access to the plenum. It's a pretty easy job now to remove and replace both halves, just a bunch of 8mm screws hold it all together. Take notes or digital pics along the way so you can pop it all back together. My only caution would be; when you have it apart, do not drop anything in the intake port! I always stuff kleenex in these while I'm working in case something slips out of my hands. Also, don't over tighten, it's all plastic. If you don't want to do it yourself, a shop should charge about an hour and a half, plus the codes must be reset and the van driven until all the monitors are ready.

SOURCE: got code p0171 system too lean (bank 1)

This is probably referring to problems with your bank 1 oxygen sensor.  Without the vehicle make, model and year I can't tell you where it is located.  However, if you replace your front oxygen sensor that should clear up the problem.  Also, if you do replace it, I always run some fuel injector cleaner through a full tank of gas at the same time.  Hope this helps!

SOURCE: have p0130 and p0133 codes 98 toyota tacoma

I would check the O2 sensor, and if it checks bad, replace it, and clear the trouble codes. If the light comes back on, you may need to check further. .