FIX, STRIP, SCRAP or sell on? End of my fuse!!

[tiffx19]

I'd not heard of that trick [turning on all electrical systems] to get a car through emissions before - thanks for sharing!

Yes, it works- first noticed it sometimes when testing, the fan would cut in and then the readings would drop down, sometimes enough to pass.. so I stared switching everything on when the readings were above a pass, and it works!

[chrisrigby]

Sounds like a good idea I will try that next time... I will be getting the inlet manifold in the next few days so will be getting a test after that... I wish I had my own emissions tester it would make things a hell of a lot easier...

Or find an identical car and swop plates for the emissions test LOL

[Stan_B]

I hate seeing threads like this, people throwing parts at a car in the hope of getting it through an emissions test..

iBlock 1 tailpipe with a rag and see if that brings it down...BET test- ... 0.7CO 650 HC 1.05 lambda. FAIL

I have read that the TT exhausts need this as the nearside tailpipe sucks rather than blows at low RPM.
The electrical load is interesting. If there is an air leak then loading the engine down to where it needs that much air might make the difference.

[Rob Bell]

I hate seeing threads like this, people throwing parts at a car in the hope of getting it through an emissions test..

iBlock 1 tailpipe with a rag and see if that brings it down...BET test- ... 0.7CO 650 HC 1.05 lambda. FAIL

I have read that the TT exhausts need this as the nearside tailpipe sucks rather than blows at low RPM.
The electrical load is interesting. If there is an air leak then loading the engine down to where it needs that much air might make the difference.

Lucky the TT I have on PS is a single outlet "Racing" version then!

[chrisrigby]

Well the inlet manifold eventually arrived after a rather long wait... So I stripped it cleaned it up and check the parts visually for any damage of signs of failure... All ready to fit so with good light in the evenings I set upon it.

The top bolts went well 13mm but the bottom ones were a little pain I can get them all 10mm bottom left no problem but the 2nd and 3rd appear to have been removed or played with before as they have been rounded off the closest socket to almost get on them was a 3/8 but I would have to hammer it on gutted!!

So my thoughts are to just replace the parts I can injectors and rail with the connections, the fuel regulator, air intake temp sensor ect... And hope that does it.

I also have noticed the I have less pressure out of the left exhaust and more on the right... So I think I may replace the back box also... Think I might buy another one soon this one is getting a royal pain

[chrisrigby]

Update.. took the injector rail off with connectors looks ok but the seals did have oil present so my feeling is that I havevan internal fault.

[Rob Bell]

Oil or a tarry residue of combustion? If the latter, that is pretty normal and not something necessarily to be concerned about...

[chrisrigby]

Well I'm thinking some gasket has gone inside some where..

[Rob Bell]

I doubt it, but there is a possibility that oil is being drawn up the breather pipes? Where did you see the oil? On the outside or the inside of the rubber injector seal?

[Ian]

Hi Chris, I've been following this post with much interest !. Having had my MGF (VVC 2000 MY) since February and chased through about a dozen electrical faults - I can sympathize with your search for the cause. From what I understand, the Emissions are too high either on idle or fast running ?. The processor should set up the fuel injection pulses proportional to the engine load, speed and temperature. Its a clever system, however the loss of a vital sensor(s) will confuse the Processor and it just gives up to a default setting. I don't think the default will pass the emissions test ?. The reasons that the emissions improve when you turn on all the electrics, is because the processor advances the ignition timing slightly, to raise the engine idle speed a bit. With the spark delivered just a few milliseconds ahead of normal, the richer mixture will burn off a bit faster.
From experience, I would check all of the electrical connections into the processor, both on the Red and Black connectors. You can look at the connectors more easily by prising off the white cover over the pins. Use a very small screw driver and prise up one end first. Once you have that off you can see all the copper female pins. If I am having a reasonable guess, the connections might be a bit loose. If the Oxygen sensor or MAP sensor is intermittent, this won't help. Also make sure the temperature sensor is connecting OK. I used a very small jewelers screw driver to pinch up the pins but just a tiny tad. This was enough to make them fit very snuggly on the male pins on the processor. The cable (4 wires) from the oxygen sensor should have some sort of electrical screening, on my MG its something very basic like heat resistant metal film. The signals from the oxygen sensor and the MAP sensor are tiny swings in voltage. Any electrical interference, such as HT leads coupled with those signals will cause problems. Hence the need for separation from the HT leads and some electrical screening. I guess MG were asking a lot of the wiring in the MGF, if there are any problems between sensors and the processor, the outputs (fuel injectors & ignition spark) will default to a non adaptive mode. I would also check the security of the loom wiring before it reaches the processor. Whoever had worked on my MG in the past unclipped everything and left cables swinging in the wind - caused intermittent connections !

Hope you get to the bottom of it !- being an electronics engineer, I always suspect the electrical side first !. Cheers.

Ian.

[chrisrigby]

I doubt it, but there is a possibility that oil is being drawn up the breather pipes? Where did you see the oil? On the outside or the inside of the rubber injector seal?

I film of oil over the injector seals.. Here's my thinking.. Everywhere I look I find oil yes I know I don't have any experience with engine building but if there is oil getting into the combustion then this would account for the high CO level..

The car is running rough with a slight misfire possibly due to some additional element in the ignition process on one cylinder I really need to do a compression test to put this thought process to bed once and for all....

In ref to the breather pipe yes some oil has been found there also.. As well as inside the air temp inlet manifold sensor positioned by injection NO1.. Some small traces inside the breathers also..

[chrisrigby]

Hi Chris, I've been following this post with much interest ! If the Oxygen sensor or MAP sensor is intermittent, this won't help. Hence the need for separation from the HT leads and some electrical screening. I would also check the security of the loom wiring before it reaches the processor.

Hope you get to the bottom of it !- being an electronics engineer, I always suspect the electrical side first !. Cheers.

Ian.

Thanks Ian the VVC is slightly different to mine.. The map sensor is a valve on the mems 1.9 so no electrical connect but I have checked cleaned this valve to the ECU didn't seem to make a difference... I have fitted a genuine lambda an increase to the reading but no pass..

There IMO has been some fettling to the electrics in the past I think as there are a few pieces within the loom the looks like its been wrapped in black electrical tape but this could be normal I haven't looked in anyone else's bay... You make a very good point about tempest there are a few connections and wire securing units that are not connected to the body of frames I will try and get them back into place..

[Ian]

OK Chris

Compression test on all cylinders very good idea. If the car was stood a long time, would the valve stem oil seals be hardened up ?. Might be causing a lack of seal more on one cylinder...

I'll leave you to investigate ! - so many of us here pooling thoughts !

Ian.

[chrisrigby]

Thanks Chaps.. an update..

I have another MGF although another MOT failure its stuff i can atually see and fix with little effort although a big list i should be MOT`d by tuesday... Sadly to save a bit of cash i will be "borrowing" some parts from this one with the intention that i will sort it out later..

I have been posted and will be moving to my new house soon so will need to be mobile for work.

By luck the new one is same year and same colour but a VVC it failed its MOT in June but more importantly it passed the emissions happt the rest is bolt on and off stuff so shouldnt be a problem for now..

sad but needed to do it.. now although i want to know whats wrong with the 1.8i what should i do with it?? sujections??

[Martin_Bmth]

Good luck, might get Mabel back to the emissions tester next week, see how she's looking after the last tweaks (not retested after getting the exhaust manifold squeaky tight and the oil change).

[chrisrigby]

Good luck, might get Mabel back to the emissions tester next week, see how she's looking after the last tweaks (not retested after getting the exhaust manifold squeaky tight and the oil change).

Well mate I would offer all the parts of mine but as we're both in the same boat could be pi**ing in the wind...

It's a shame as the whole car is in good nick... Maybe convert to electric?? Seen the one in Poole Quay wonder how much that would cost??

[chrisrigby]

viewtopic.php?f=9&t=15483&p=113489#p113489

Sadly time has ran out for this one...

[Martin_Bmth]

Good luck, might get Mabel back to the emissions tester next week, see how she's looking after the last tweaks (not retested after getting the exhaust manifold squeaky tight and the oil change).

Well mate I would offer all the parts of mine but as we're both in the same boat could be pi**ing in the wind...

It's a shame as the whole car is in good nick... Maybe convert to electric?? Seen the one in Poole Quay wonder how much that would cost??

Not seen a electric one, interesting im picking up a inlet manifold with known good injectors and a maf sensor so i can catch up your diagnosis so im not far behind ya on the emission trail. Will be fiddling close to a emissions machine in a week or two. Hopefully will have some bits left and will get an answer. Only thing ive not got is access to an obd reader for mems 1.9 if its the computer having a laugh.

[talkingcars]

Finding the rounded bolts would have encouraged me to remove them to see why they have been messed with.

The correct TPS reset is
Switch to ign 2
Fully and smoothly fully depress and release the gas peddle 5 times.
Wait for the stepper to do it's stuff.
Then start the engine.

[chrisrigby]

Finding the rounded bolts would have encouraged me to remove them to see why they have been messed .

Mate I would have done it but I couldn't see how it would have done this? Other than dropping the engine on the subframe but this would take an age and I don't have much time. It's very tricky to even get the 13mms socket on a 6" Extention without the bolts not fitting the same size..

I thought about smashing on a slightly smaller size but again difficult to do this with the access available. It's not possible from underneath either.