Richard First it's well worth going over all the connections and the earth points, and look for any place where the EFI harness may have chafed
I had a similar problem some years ago. Over a period of a year I noticed the odd momentary loss of power, maybe once every month or two. Eventually it became much worse over a week or so, and then one day the +8 refused to start. I spent a few days trying to identify the problem, until the light turned on, and I changed the rotor arm. The hesitation was normally when the engine was under some load, and under these conditions you need a bit more spark, and thus more stress on the ignition, and the dodgy rotor arm would start to break down. I am not sure about the AFM, I suspect that the ECU may just use a default map and run the engine a bit rich (as it does if your oxygen sensors aren't working) The AFM is floating, it is not earthed, and there have been odd cases of rubber heater hoses touching the AFM and causing issues (the rubber of the hose being slightly conductive), but I don't think that causes complete loss of go. There is another fault that can cause the loss of the accelerator, if the signal from the throttle position sensor goes out of range the ECU sets the engine at a fast idle, and ignores the throttle. Normally this needs a power down of the ECU and power back on to recover, but I don't know what the Tornado does in these circumstances. The throttle position sensor is a potentiometer, and has a resistive track which the wiper goes over, eventually the commonly used areas of the track get worn, and the wiper gets an intermittent connection, and the ECU sees the signal as out of range. Personally I would change the rotor arm on the basis that its cheap, and then work on from there I do have a couple of code readers, if you should be near Bracknell again, but the 14CUX ECU doesn't remember fault codes for ever, so you need to check the fault codes after the event, but before turning power off. There is a memory retention power feed for the ECU but I am not sure that MMC feed constant power to this, and its certainly lost if the red key is turned off. Good luck Mike Smith From: Richard Jones [mailto:[email protected]] Sent: 30 June 2012 12:48 To: mogtalk2 Subject: [mogtalk2] One for the +8 doctors Had a slightly odd one yesterday. Left Kent for Theale, Berks just around 5.15 am for a work appointment in Theale, Berks - lovely blue skies. I had a full tank of Esso (95) from my regular garage. Uneventful journey as far as Bracknell, few showers of rain and heavy cloud cover, so had dipped beams on and wipers intermittently; Friday traffic not that bad so cruised with the outside lane traffic which in the +8 is around 3,000 rpm give or take. As I needed to get back home later without stopping, I topped up the tank at the Shell garage on the A322 passing through Bracknell, another regular stop (again 95 octane) and the headed out of Bracknell on the A329M still overcast so had dipped beams on again (mix gear work, accelerate, cruise, accelerate, cruise for about 5 miles) and turned off onto the M4 towards Reading. I merged into the traffic and sat on the inside lane for a while as traffic was heavy at around 65-70, then in 5th geared accelerated to move into middle lane, but the engine fluffed and wouldn't accelerate. I eased off and car continued to cruise normally. I repeated this 3 times with same result and then at the next go it accelerated as normal. I then slowed and tried again and had the same problem 3-4 attempts and then it cleared again and I then ran on without any more problems and exited the M4 at Theale drove through the business park as normal and arrived at our offices. I left at 3pm and drive home in nice sunshine without any problems whatsoever apart from a few traffic holdups. Not sure where to look and if this was temprary, or signs of a problem brewing. Don't really know if this is fuel or sparks related, or which sensors may be involved, or some water/dirt in the fuel system . I had the fuel related relays changed last year, fitted a new Odyssey PC925 (28Ah) as recommended by this group for the last 800 miles (ammeter was shows a good rate of charge (14 no load 13.5 with dipped beams and demister fan), It was serviced back in May, so not sure where to go next. Its a '95 3.9 hotwire with twin Librands exhausts, Tornado chip, K&N filter and the fuel pressure runs a bit higher than standard as I have a remote fuel pressure valve fitted. All these parts have been on for 2-3 years. Thinking back over the 4 years I have had the car, very very occassionaly (I mean 2-3 times in 4 years) I have had a very minor cough when accelerating under load, but this was a pronounced wheeze in comparison. It felt more fuel related to me, maybe a MAF meter malfunction? Any thoughts? Richard M800RGN+8 View posts on The Mail Archive http://www.mail-archive.com/[email protected]/ Modify<https://www.listbox.com/member/?&;> Your Subscription [https://www.listbox.com/images/listbox-logo-small.png]<http://www.listbox.com> ------------------------------------------- View posts on The Mail Archive http://www.mail-archive.com/[email protected]/ [http://www.mail-archive.com/[email protected]/] Modify Your Subscription: https://www.listbox.com/member/?member_id=22459785&id_secret=22459785-4a39ddf8 Powered by Listbox: http://www.listbox.com
