Project Celsior, The Story So Far.

[VijayA]

Perhaps a daft suggestion but if you put the ecu from your working Celsior do the codes still flag up....if they don't that rules out the o2 sensors and suggests the new ecu may not be compatible...or is this too dangerous to consider?

[steve2006]

Perhaps a daft suggestion but if you put the ecu from your working Celsior do the codes still flag up....if they don't that rules out the o2 sensors and suggests the new ecu may not be compatible...or is this too dangerous to consider?

Yes,

I was tempted to do that but as you mention the last thing I want to do is kill my working original ECU from my fully functional Celsior.

The "faulty" ECU did have the leaking capacitor problem and I gingerly opened my good one and found no damage so left well alone.

I find sometimes I;m going around in circles one example is I measured the O2 sensors heater resistance from the ECU and they read open circuit on both cars! Now I know my runner is fine so why the same readings?

Looks like I'm going to have to get down low and dirty to check them under the car at the connectors, what would amuse me is if they are both disconncted. Plus the engine management light is not illuminated which with 2 duff sensors you would think it would be.

[VijayA]

True unless the new ecu also has an issue ? It would seem that even non leaky capacitors are known to be faulty and that really is the only weakness in our cars. One more things ..both sensors fail at the same time ? Is that really possible? No really the last thing the ecu controls everything so what damage could be caused to it bearing in mind the new ecu hasnt blown itself up......you could try the new ecu in your working car to see if any faults are transferred. Did I just confuse you and me at the same time?

[steve2006]

When I get the chance I'm going to fit the newly purchased replacement in my working Celsior ( we'll call this from now on Celsior A) and if this runs OK with it fittted this would eliminate any fault with this ECU.

So then it is back to checking the O2 sensors on the misfring Celsior ( we'll call this from now on Celsior B.

If anyone needs any parts off my other 1997 Celsior ( this is now Celsior C) please let me know :)

[IHgs300]

What colour is the rear armrest in celsior c Steve?

[steve2006]

What colour is the rear armrest in celsior c Steve?

It's an all blue interior including the rear armrest Ian.

[IHgs300]

Typical, was hoping you would say black...

[steve2006]

Ar sorry, Celsior C the 1997 Breaker does have a black interior and armrest, Celsior B is blue and Celsior A is beige.

[wackyjim]

Hi Steve. Did you manage to get the the fuel flap sensor switch off car C ?

Jim

[IHgs300]

Ar sorry, Celsior C the 1997 Breaker does have a black interior and armrest, Celsior B is blue and Celsior A is beige.

Pm sent Steve.

[steve2006]

Hi Steve. Did you manage to get the the fuel flap sensor switch off car C ?

Jim

Arr sorry Jim I 1) forgot initially,2) been at work every days since and 3) inbetween work having to transport other half to hospital as her mum is in there.

Will take a look later today for you,rather that than mow the grass :)

So today I am driving around in car A, still working on the misfire on car B and removing the fuel flap solenoid and getting the rear seats from car C.

Good job Jim has collected car D :)

[IHgs300]

See you soon Steve and thanks again. :)

[steve2006]

No problem Ian.

Jim I've emailed you re solenoid, taken off,packaged ready to send tomorrow.

[wackyjim]

Thanks Steve..That's me just in the door so just checking up on all the latest posts and e-mails. Just let me know what I'm due you for parts and postage :)

[steve2006]

Ok back to the topic :)

Today I have been working on misfiring Celsior B.

This morning I checked the cam belt timing and it was spot on and since swopping over the ignitors and back the misfire at idle seems to have gone but it is not reving cleanly, it has a stutter and roughness unlike a V8.

The 2 codes for both O2 sensors keep flagging up on a diagnostic check but the management light remains out in normal running mode.

Following the checks in the workshop manual I compared results for checking these on both cars and they were the same figures.

One thing I have noticed on the poorly Celsior is there seems to be a lot of water coming out the exhausts during warm up and the engine warms up very quickly and smells hot even though the gauge is centreline.

The exhaust also smells rich in fuel.

Just to eliminate the possiblility I am going to perform a compression test on the engine but I doubt both CHGs have failed together.

I have also checked the CTS on both cars and the results are both within specification.

I now have a new theory which will be checked out on my next attack, initially I had codes for both O2 sensors and the AFM but now the latter has gone, the common denominator of all three is the earth connection E1, now do I have an earth off?

Time will tell.

Just realised the exhaust runs into one section at the Y piece so could be a Head gasket problem on just one bank mmmmm.

[steve2006]

I borrowed a compression tester from the garage my company uses and all came up OK around the 200PSI mark so no gasket damage.

What I did find when removing the plug leads is 2 of them on one bank had the plug connector pushed halfway down the rubber moulding meaning they would not be in physical contact with the plug itself.

Not had time to put everything back together tonight be maybe finally found the reason for the mysterious misfire.

[The-Acre]

I borrowed a compression tester from the garage my company uses and all came up OK around the 200PSI mark so no gasket damage.

What I did find when removing the plug leads is 2 of them on one bank had the plug connector pushed halfway down the rubber moulding meaning they would not be in physical contact with the plug itself.

Not had time to put everything back together tonight be maybe finally found the reason for the mysterious misfire.

I bet you slept soundly knowing the head was ok!

[steve2006]

Yes it was a relief so carried on today, refitted it all back together and although there is no misfire and the tickover is fine there is a distinct lack of power delivery when driven.

More strangely or not,the 2 fault codes have not reappeared after reset as I now get the continuous flashing light when the diagnostic link is in place.

Strangest set of symptoms I've ever worked on with a car I seem to eleiminate one problem and still have another hiding behind it.

With no faults codes to guide me it looks like a bit of component swopping coming up, 1st is the MAF.

10mm at the ready,steady,go!

[IHgs300]

She's definitely worth the time Steve, Take it the plug leads didn't cure it then?

[steve2006]

She's definitely worth the time Steve, Take it the plug leads didn't cure it then?

No all fitted back correctly this time and made little difference, swopped the MAF same result.

[IHgs300]

With you mentioning a fuel smell, have you tried swapping the fpr? Thinking back to my cosworth days, i once had a similar problem and traced it to overfuelling. Bit rich on tickover but higher the speed the rougher it ran.

Might be way out but who knows?

[steve2006]

Finally I think I have got to the bottom of the misfire.

Yesterday I ran the engine up to temperature and there were no codes being shown however this morning I rechecked and 21/28 both O2 sensors were once again present.

So with the front end up as high as possible I removed the sensors and sure enough both have no heater continuity and are therefore defective.

What I still cannot understand is why even with codes present did the management light not come on and why have both O2 sensors (original Denso ones) failed at the same time.

The only explanation I can think of is the confirmed original defective ECU has somehow burnt out the heaters in the sensors,pleased I didn't try it in my running one now!

Replacements have been ordered should be with me Tuesday.

[Bluesman]

Finally I think I have got to the bottom of the misfire.

Yesterday I ran the engine up to temperature and there were no codes being shown however this morning I rechecked and 21/28 both O2 sensors were once again present.

So with the front end up as high as possible I removed the sensors and sure enough both have no heater continuity and are therefore defective.

What I still cannot understand is why even with codes present did the management light not come on and why have both O2 sensors (original Denso ones) failed at the same time.

The only explanation I can think of is the confirmed original defective ECU has somehow burnt out the heaters in the sensors,pleased I didn't try it in my running one now!

Replacements have been ordered should be with me Tuesday.

Is it worth saying Halleluiah yet? :hocus-pokus: :hocus-pokus:

[IHgs300]

Great news Steve, fingers crossed for you.

[steve2006]

Well it's been a while since my last update but due to work commitments things have moved into the slow lane.

There are now no stored codes after the O2 sensor replacements and the engine warms up and idles spot on.

However there is still hesitation when the engine is revved and the performance is flat and unresponsive.

So after further investigation I am now looking at a clogged exhaust system possibly due to collapsed cats,from the misfiring issue and the duff O2 sensors.

To check the exhaust pressure the O2 sensor needs to be removed and a special gauge put in its place to measure the pressure.

These are a mere $40.00 in the USA but of course 3-4 times this in our fabulous country so I have ordered a vacuum/pressure gauge (+/- 15PSI) from an eBay seller for around £12.00 and then will convert one of the old O2 sensors into a suitable connector to the gauge.

To be continued...........