One Thing After Another! (P0172) System Running Rich.

[JoeyJoe]

I used to drive an MG ZR that had less problems in the couple of years that I've owned it than my Celica that I've had for a month!!

Everything is stock at the moment. We replaced the radiator after that was leaking, and the car has been fine for a good couple of weeks, but yesterday the engine light flashed up after hitting high RPM with P0172.

I cleared it straight away and it was fine, till it came back on this morning during normal morning commute.

Any idea's on what I should check first?

[Mocambique]

get someone to check your exhaust sensors - on the computer

[JoeyJoe]

get someone to check your exhaust sensors - on the computer

Is that really the best thing to do first of all? No wires to wiggle in the engine bay?

[Devon Aygo]

Toyota diagnostics point to a possible fault with one or more of the following:

* Exhaust gas leakage, check exhaust manifold, catalyst, exhaust joints and oxy sensors for exhaust gas leak

* Fuel line pressure fault, check and confirm correct fuel pressures

* Injector leakage, blockage

* Heated Oxygen sensor bank 1 sensor 1

* Manifold absolute pressure sensor

* Engine coolant temp sensor

The last 5 items would need specialist diagnostic equipment, as you have just worked on the coolant system it might pay to just check that the coolant system has been fully cleared of airlocks as the Celicas are notoriously hard to bleed fully and air around the coolant temp sensor would fool the car in to thinking its colder than it actually is making the ECu over fuel and run rich for too long

[JoeyJoe]

Thanks,

We also dismantled the idle air valve to fix an issue with the idle. That problem was fixed but this one came along a week later.

I'm sure the coolant system is fine. I've checked the temperatures and it warms up nicely and sits at a good temperature.

Only had it since November, and looks like I'm going to be getting rid of it soon :(.

[ToyotaAuris]

Thanks,

We also dismantled the idle air valve to fix an issue with the idle. That problem was fixed but this one came along a week later.

I'm sure the coolant system is fine. I've checked the temperatures and it warms up nicely and sits at a good temperature.

Only had it since November, and looks like I'm going to be getting rid of it soon :(.

Lots of dodgy people selling cars which are full of problems!!!

[JoeyJoe]

Actually the car was fine when bought. Couple of known issues, but the issue i have now are new. I have almsot every MOT paper and just about every receipt from every repair the car has had. It's just high mileage at 150k

[Lcdch02]

had my Celia VVti from new bought in 2000 ...last MOT only just passed the emission test so this year looked on Ytube to locate and take advice regarding reducing the emissions.....Added Slick 50 to the engine Oil...cleaned MAF sensor ( Mass Air Flow} with MAF spray..( located on the air filter) fitted new air-filter ( £2.80p ) from Halfords..and cleaned piston bores, valves and sensor on exhaust using similar spray...added cleaner to my fuel ...flowed all the instructions on all of the products...reset my engine light with a tool purchased off eBay for about £20...( Hand held Engine Fault Diagnostic Scanner Code Reader)....Took it for its MOT and passed with flying colours.emissions perfect....

....Good luck....