Engine fault code

[higpots438]

Hi i have just put 200 cell cats on my 2007 Aston v8 vantage. extensions were installed to the lambda probes but i am still getting engine fault codes . My main concern is will this stop any other fault code appearing on the dash. ie Low oil pressure or similar. Any ideas on how to resolve this problem

[bogie]

Buy a generic OBD II dongle for your phone or a dedicated reader, no more than £30-40. You can read and reset the codes. Keep a record of the codes its showing and if the same ones repeat over time, get it investigated further.

The codes are standard OBD II so you can find them online.

[PatCub]

If you press the read button it will clear the message, but you will still have the check engine light on until the fault is cleared.
Any additional faults will cause a new message to appear. More serious faults like oil pressure have a dedicated warning light.

[telum01]

Oil pressure will have a red warning triangle instead of orange.
As said above, press the Read button to cycle through messages.
What cats are you using? What fault codes are you getting?

Edited by telum01 on Thursday 17th May 01:12

[higpots438]

Hi i am using 200 cell cats from a company called Top Gear.I am getting a engine fault code and a emissions code over the digital speedometer. Thanks for the prompt replies.

[BamfordMike]

higpots438 said:

Hi i am using 200 cell cats from a company called Top Gear.I am getting a engine fault code and a emissions code over the digital speedometer. Thanks for the prompt replies.

Plug a diagnostic fault code reader into the diag port nearest to the steering column.

If the pcode is P0420 or P0430 the reason is lack of catalyst combustion gas conversion / efficiency and the only way to cure that problem is via ECU reprogram or replace with a cat with one which doesn’t suffer the same problem. Some aftermarket cats are not sufficiently loaded with precious metal content and will not convert gas sufficiently and will trigger an efficiency problem, whilst some aftermarket cats are well loaded with precious metal content (£costs more to make) and will not suffer the same problem.

If the problem is a P13xx or P15xx it’s a lambda sensor issue.

The concept behind the idea of extending / lifting the lambda sensors out of the exhaust gas flow to somehow fool the system into thinking the catalyst gas conversion is fine, is a complete daft practice concieved by a moron. All that lifting the sensors will do is slow the response of the signal back to the ECU which, surprise-surprise, is the prime reason most standard V8’s ping a fault code, especially as the sensor ages!
Also, the height clearance between top of sensors and chassis isn’t much at stock, so extend the sensors and you risk ramming the wiring into the chassis. That will blow fuse 18 in the under bonnet fuse box which runs lambda sensor and variable cam timing system and cause complete loss of power - seen that happen all too often.

The moral is installation of sports cats without several Pcodes turned off via an ECU remap, whilst someone might get lucky and have no codes, is in reality asking for continual fault codes which will have to be lived with if there is no access to an ECU reflash.

To answer a question you raised in the first post.
If the check engine light is on for the cat related issue, and then you have, say, a misfire on any cylinder or a MAF sensor failure, because the check light is already illuminated for the cat / lambda issue, any new subsequent faults you will not know anything about.