Pre-cat removed - now Malfunction warning lamp on!

[CeeJay72]

Hi All

I just had the Pre-Cats removed (from my low-milage (27,000 miles) 2001 Roadster) and replaced with a SS Manifold.  However now the Malfunction Warming Lamp is always on.  The garage state that this is because I have removed the Cats so it'll always remain lit...

Has anyone else had this problem?

Regards
Craig.

[nathanMR2]

Unlikely. Need to get the code read really. They could have damaged a sensor when getting it out.

Where abouts are you?

[Anonymous]

Did you disconnect battery for 25mins to reset ECU to relearn fuel trims after you gutted manifold?

[CeeJay72]

Unlikely. Need to get the code read really. They could have damaged a sensor when getting it out.

Where abouts are you?

In just outside Perth...

[CeeJay72]

Did you disconnect battery for 25mins to reset ECU to relearn fuel trims after you gutted manifold?

No I didn't try that - I'll give that a try!  Will this mean I'll have to get the code for my stereo as I imagine it'll need a constant feed?

Craig.

[Anonymous]

Not heard of any roadster having a stereo code on their standard Toyota stereo.

[Anonymous]

If you fancy a drive, i have a code reader.

[CeeJay72]

If you fancy a drive, i have a code reader.

I may take you up on that!  I'll try resetting the ecu first.  As for the stereo, I thought it would need a re-code if it lost power.  Most of the cars I've had in the last 5 years have had this so I just thought that this would be the same deal.  Right - I'm off to disconnect the battery...

I'll keep you all posted- and thanks for all the replies - its much appreciated!

Regards
Craig.

[CeeJay72]

Hi All

Pulling the plug on the battery did the trick!  I've spent 20 years re-booting PC's but  thats the first time I've had to re-boot my car!

Many thanks for all the help - that'll save me a tick to my local Toyota Garage.

Regards
Craig.

[Anonymous]

If the fault is still there, the cel will return.

[roger]

If the fault is still there, the cel will return.

Especially if its got nothing to do with the O2 sensors or manifold. If it does reappear you MUST get it read, one way or another.

[CeeJay72]

If the fault is still there, the cel will return.

Especially if its got nothing to do with the O2 sensors or manifold. If it does reappear you MUST get it read, one way or another.

Sigh - the warning came back...  New it was to good to be true!

OK so I've bought myself a Fault Reader and I get the fault number P0141 which in the manual that came with the fault reader is shown as a 'O2 Sensor Heater Circuit Malfunction'.

Is this sensor separate to the now discarded toyota manifold?  Or am I looking at having to re-fit the old unit (Which I doubt is the case as I know plenty of people are using non-stock manifolds!).

I take it this will lead to another wallet battering?

Regards
Craig

[Anonymous]

It the post cat sensor that has gone,its the one at the bottom just after the cat and connector is at the top near left hand rear light.They take 5 mins to change,get yourself on this group buy and save a few quid.   l viewtopic.php?f=36&t=28730 l

[51ice]

If the fault is still there, the cel will return.

Especially if its got nothing to do with the O2 sensors or manifold. If it does reappear you MUST get it read, one way or another.

Sigh - the warning came back...  New it was to good to be true!

OK so I've bought myself a Fault Reader and I get the fault number P0141 which in the manual that came with the fault reader is shown as a 'O2 Sensor Heater Circuit Malfunction'.

Is this sensor separate to the now discarded toyota manifold?  Or am I looking at having to re-fit the old unit (Which I doubt is the case as I know plenty of people are using non-stock manifolds!).

I take it this will lead to another wallet battering?

Regards
Craig

P0141 is the sensor Bank1 Sensor2 same one as mine at the very end of exhaust.
 l viewtopic.php?f=11&t=28827 l

Two options,

1. Check the resistance of the 2 black wires(heater) if is open or less than 11 ohm. Replace it.
2. Buy a big resistant around 12 ohm and the current should be higher than 1Amp. Cut the black wires and connect them to the resistant directly.

[CeeJay72]

Especially if its got nothing to do with the O2 sensors or manifold. If it does reappear you MUST get it read, one way or another.

Sigh - the warning came back...  New it was to good to be true!

OK so I've bought myself a Fault Reader and I get the fault number P0141 which in the manual that came with the fault reader is shown as a 'O2 Sensor Heater Circuit Malfunction'.

Is this sensor separate to the now discarded toyota manifold?  Or am I looking at having to re-fit the old unit (Which I doubt is the case as I know plenty of people are using non-stock manifolds!).

I take it this will lead to another wallet battering?

Regards
Craig

P0141 is the sensor Bank1 Sensor2 same one as mine at the very end of exhaust.
 l viewtopic.php?f=11&t=28827 l

Two options,

1. Check the resistance of the 2 black wires(heater) if is open or less than 11 ohm. Replace it.
2. Buy a big resistant around 12 ohm and the current should be higher than 1Amp. Cut the black wires and connect them to the resistant directly.

Life of Bryan / 51ice thanks for the replies.

I'm now in a quandry as I'm happy to replace a sensor but as for checking checking the resistance (and or adding a new resistor) I'm a wiring novice so that one worries me a bit!  I think if thats needed I might call in an expert!

Regards
Craig.

[Anonymous]

Then just replace it with the group buy "plug and play" which should take you 5 mins.

[CeeJay72]

Then just replace it with the group buy "plug and play" which should take you 5 mins.

Ok - I think thats what I'll go with.

Can I drive the car while this sensor is faulty?

C.

[Anonymous]

Yeah it doesnt affect fuel trims etc but if something else goes that isnt obvious you will have no way of knowing,might be worth keep reading/clearing code every day as you have a reader till new sensor is fitted.

[CeeJay72]

Yeah it doesnt affect fuel trims etc but if something else goes that isnt obvious you will have no way of knowing,might be worth keep reading/clearing code every day as you have a reader till new sensor is fitted.

I just re-plugged in the reader just to check that it was a 141 error, and it seems I also have a PO171 /PO174 error(s) as well (They where there all along - I didn't notice the scroll down message).  I've just looked those up as well and its a 'System too Lean' error.  

B*gger - is this all linked to the O2 Sensor?

C.

[aaronjb]

Sounds to me like you have an air leak somewhere in the exhaust system north of the O2 sensors (probably at the manifold gasket)

[CeeJay72]

Sounds to me like you have an air leak somewhere in the exhaust system north of the O2 sensors (probably at the manifold gasket)

I suppose that would make sense - after all the problem started after I had the SS Manifold fitted.  So - plan of action:

1) Get manifold checked for a leak.

If no joy:

2)  New O2 Sensor

Again thanks to all how have taken the time to reply - much appreciated - I hope I can return the favour 1 ay.

C.

[Anonymous]

Sounds like you should take it back to garage that removed precats then to put their work right.

[CeeJay72]

Sounds like you should take it back to garage that removed precats then to put their work right.

I'm not going to blame the garage as they've done a lot of work on my cars over the years and have been pretty spot on.  However when I bought the SS manifold I did have my doubts about the supplied gasket - it seemed to my untrained eye a little inflexible, but I thought - ''they wont sell a gasket with the manifold unless its OK'.  It may be that this is the weak link - and if so all I need is a new gasket.  

I'll keep you posted!

Regards
Craig.

[Anonymous]

New Toyota one for sale here:  l viewtopic.php?f=37&t=28829 l

[aaronjb]

Sounds like you should take it back to garage that removed precats then to put their work right.

I'm not going to blame the garage as they've done a lot of work on my cars over the years and have been pretty spot on.  However when I bought the SS manifold I did have my doubts about the supplied gasket - it seemed to my untrained eye a little inflexible, but I thought - ''they wont sell a gasket with the manifold unless its OK'.  It may be that this is the weak link - and if so all I need is a new gasket.  

I'll keep you posted!

Regards
Craig.

If the gasket was one of those 'dotty metalised card' things then it could be that.. if it was a bimetallic sheet with a lip around each hold then it's the standard Toyota item and should seal fine..