Engine stalling when throttle applied

Technical Area Engine, Transmission, Exhaust etc
1
  1. My model of MX-5 is: 2005 mk2.5 icon
  2. I’m based near: Chesterfield

Hi all. This morning I replaced my crank position sensor (gapped using the credit card trick) as I noticed it was cracked when I did my timing belt a few months ago. As I was putting the tools away, I started the car and let it come down to idle to make sure it was alright and gapped correctly.

However, about 30 mins later when I went to do a quick test drive, as I started moving the engine cut out. I thought maybe I’d just stalled it, so I started it again, drove down the road and then it cut out again.

I tried starting it again but this time, it caught and then stalled when I pressed the throttle. I managed to get it started again by:

  1. Turning to ignition
  2. Unplugging the MAF
  3. Starting the car. It was rough and probably not driveable, but it wasn’t cutting out.
  4. Plugging the MAF back in.

This obviously caused a CEL, but I managed to get home. I though I was in the clear, but when I was straightening up on my drive, it cut out once again. I tried the same trick again and it worked for a shorter duration. Now whenever I start the car it either: a) idles, then stalls when I apply throttle or b) stalls straight away.

I checked the TPS on my code reader and it seems to be accurate.

I made sure everything I unplugged or removed has been re-installed (crank sensor, MAF, Air temp, breather hose).

I’m thinking this is either a MAF or TPS issue, but I wanted to get your guy’s thoughts on it first.

Cheers.

2

Have you tried refitting the original crank sensor as I assume it was running fine with that on. Seems a strange coincidence for a MAF or TPS to suddenly give up for no apparent reason while changing the cranks sensor.

3

Seems to have been an issue with the new crank position sensor I installed. Swapped the old one back in and it’s fine. I’ll give mx5 parts a shout and ask for a replacement.