Cleaning AFM

[griffter]

Car spluttered and died twice today on the motorway, prompting me (once I'd got it restarted) to turn round* and get the banger to go to work in instead.

I'm working my way through the ususal suspects, but wondered - it is possible to clean the air flow meter at all? As I understand it hot wire types are generally self-cleaning and should be left well alone for fear of damage/contamination. Any comments?

* At the next junction

[K4TRV]

My pennyworth would be to leave the AFM alone (or go to RPI web page and set yours up as per their instructions: www.rpiv8.com/carbs-2.htm )

Sounds more like you've a bad connection with fuel pump or ECU connector.

What else have you checked....you say general suspects, but I've never seen AFM on anyone's list. Stepper motor for tick-over problems - dizzy for general running/starting. For me it's a fuel pum/connector problem - but that's just my view

Trev McM

[griff430]

I had the same sort of thing with mine. It turned out to be a dodgy 'engine run' relay in the passenger footwell. I changed the fuel pump relay at the same time, as they were only about 8 quid each. The problem went away for a while, until I thought it would be a good idea to tidy the mass of wires in the footwell. I moved them with the engine running and it cut out. Once again I traced it to the engine run relay, but this time it was down to a bad connection in the relay holder. Once that was sorted, it seemed to be OK.

[griffter]

K4TRV said:

My pennyworth would be to leave the AFM alone (or go to RPI web page and set yours up as per their instructions: www.rpiv8.com/carbs-2.htm ) Sounds more like you've a bad connection with fuel pump or ECU connector. What else have you checked....you say general suspects, but I've never seen AFM on anyone's list. Stepper motor for tick-over problems - dizzy for general running/starting. For me it's a fuel pum/connector problem - but that's just my view Trev McM

Thanks!

I've overhauled all engine bay electrics (ie every connector cleaned and remade) and the fuel pump wiring since buying the car as I bought it with an intermittent misfire. I found about 7 things wrong and thought I'd cured it!
What I haven't managed to do yet is any of the electrics behind the dash or the fuse box/relays.
All earths are sound, but again, I haven't had a chance to do the two on the transmission tunnel. I've done 1500 miles in it since the overhaul with no significant problems, but today knocked my confidence a bit. It felt more like fuel starvation than a sudden cut in power.
I'm happy with all the ignition side of things bar the ignition amplifier - a bit of an unknown quantity. I had one go on a Rover once with similar symptoms and the cure was to re-fit it with new heat-conducting paste. So that's the first thing I'll try.
Next is playing with the fuel pump and ecu (?) relays. These look well seated and are greased, as is the ecu connector. The car seemed to misfire then die over the course of 20-30 seconds. I don't get the imnpression it was a loose connection which would probably be more of a sudden cut out? Also the fuel pump energised immediatley on turning on the ignition again, and the car started OK after 2 or 3 longish turns on the starter (5 secs or so).

So I'm thinking dodgy sensor (maybe coolant)? Or AFM on the way out?

I guess it's possible the fuel pump relay went and the car ran on line pressure for a short time, then died. Of course all the way home it behaved faultlessly...

[turtle400]

I couldn't get my griff fuel pump to prime after I'd removed the fuel rail. The ignition lights were on, it turned over but the familiar buzzing noise whilst priming was absent. It turned out I'd forgotten to reconnect the earths on the top of the engine (between the rocker covers on the passenger side). Perhaps your problem could be a poor connection here?..... Only a thought.

[griffter]

turtle400 said:

I couldn't get my griff fuel pump to prime after I'd removed the fuel rail. The ignition lights were on, it turned over but the familiar buzzing noise whilst priming was absent. It turned out I'd forgotten to reconnect the earths on the top of the engine (between the rocker covers on the passenger side). Perhaps your problem could be a poor connection here?..... Only a thought.

Thanks, but this is one of the many earths/connectors in the engine bay I have cleaned and remade. I've just found a replacement fuel pump relay - and I'm coming around to thinking it might be that... fingers crossed.

Found a reference to cleaning the AFM on the Chim forum, but I guess it's not a common thing to do!