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MG MGF Technical - Engine electrical fault ( I think )
|Can anyone help with diagnosing what I think is an electrical fault with my engine ??|
It started last night with a slight misfire when setting off and in first or second gear when accelerating which I thought was a plug going but within a few miles it cut out altogether and will not start, not even a cough and a splutter….
The battery has recently been charged and is okay so I think it could be coil, leads or even engine management system, also no loss of water or oil in water so I think that rules out HGF…..Any ideas out there ??
1. 1.8 i or VVC ? If 1.8 i check distributor / rotor for cracks ,condensed water etc. If the car is old new parts here is a must. This also goes for the original OEM ignition cables. Do NOT replace with original but buy silicone insulated that lasts longer. Might even be cheaper than original...
2. Almost dead battery charged in situ with power charger, i.e. with both cables still attached to battery when charging ? Could in a worst case give too high voltages for some of the electronics..
3. Bad contact at the fuel pump crash switch ? Reset (press) a few times as shown in manual.
4. Even if some part(s) of the sensors fails there is usually a "limp home" setting in the MEMS so if that is the course the engine would run - but at limited power..
5. Clogged fuel filter on an old high milage car ? Any smell of unburnt fuel at the exthaust when trying to start ?
Just a few hints , others will fill in !
Regards , Carl.
|Carl.. Thanks for ideas..|
The car is a 1995 1.8 and I did charge the battery the night before last while it was still connected so it could have done some damage but I had traveled about 70 miles before the fault started..
I don't think it's fuel related but it could be,as I did run the fuel tank down to the red but then did another 10 miles before the fault appeared.
I have not had time to remove the engine cover to check any components yet but did try to start it this morning ( morning after ) and it did not even try, this is what makes me think it is electrics..
|Had this, been there, got the T-shirt dirty! ;o)|
Same fault on my Jan 96 1.8i. I discovered that despite a full MG service history, that the rotor arm and cap were still the originals (time stamped in September, 1995). They degrade with time without externally looking too awful - Dr Dave tells me that he sees this alot in his workshop.
Replace with new parts and normal service will resume (only cost a few quid from either Halfords or your MG parts department). Also take the opportunity to replace the ignition leads if they are still the original items (Brown and Gammons sell the excellent magnecor items).
All pretty easy to do yourself once the engine cover is removed. :o)
|Thanks Rob !|
I've been down to Halfords ( leads and plugs but no cap etc 33 pounds) and then to local MG dealer for Cap and rotor arm ( 25 pounds ) so all set for replacement tonight and hope to be back to normall..
I found some other usefull stuff on the archive about MEMS throttle postion sensor and fuel cut out switch so I'll check those out as well..
This thread was discussed on 09/05/2002
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