Very occasional misfire

AndyJacobs · 6th April 2018, 12:19

I seem to be frequenting this place more and more lately.

My ZT 190+ has started misfiring (I think). It happens about once a month or so. I do about 400 miles a week so we're talking very intermittent.

There doesn't seem to be a pattern. It went through the snow and temperatures of -6 without so much as a cough. But it happened before and it just happened again this morning. This morning, I was cruising along at about 60mph. Straight road, pretty flat, not too cold, dry, just filled up with Premium unleaded about 80 miles ago. All of a sudden, there's a loss of power like it's misfiring. Not complete loss of power, you can feel it and it gives that "Oh golly (Was a slightly naughty word but the forum changed it!), it's going to break down" feeling in the pit of your stomach. Dip the clutch, give the throttle a jab. All sounds good. Clutch out, still missing.

This took place over about 10 seconds and then the problem disappeared and I did another 20 miles or so to finish my journey without it happening again.

Spark plugs? Coil packs? Something more sinister?

Cheers
Andy

trikey · 6th April 2018, 12:47

Have you had the belts replaced recently

AndyJacobs · 6th April 2018, 12:50

Nope. But I'm going to soon. Are you saying that the belts might need replacing? Or that the problem could be caused by having the belts replaced?

I found a local place that seemed to specialise in MGs. I gave them the car to have the belts done and get it through the MoT. They got it through the MoT but I think they got nervous about changing the belts. I e-mailed another place on Tuesday but haven't heard back. I'm just trying to find somewhere local (ish) before I go further afield.

trikey · 6th April 2018, 14:24

I ha e seen a few where the belts have been done and the small black earth wire has been left unattached from the rear bank, this tends to make the ecu a very unhappy boy!!

6th April 2018, 12:19	#1
AndyJacobs Regular poster MG ZT 190 Join Date: May 2013 Location: Andover Posts: 73 Thanks: 14 Thanked 5 Times in 4 Posts	Very occasional misfire I seem to be frequenting this place more and more lately. My ZT 190+ has started misfiring (I think). It happens about once a month or so. I do about 400 miles a week so we're talking very intermittent. There doesn't seem to be a pattern. It went through the snow and temperatures of -6 without so much as a cough. But it happened before and it just happened again this morning. This morning, I was cruising along at about 60mph. Straight road, pretty flat, not too cold, dry, just filled up with Premium unleaded about 80 miles ago. All of a sudden, there's a loss of power like it's misfiring. Not complete loss of power, you can feel it and it gives that "Oh golly (Was a slightly naughty word but the forum changed it!), it's going to break down" feeling in the pit of your stomach. Dip the clutch, give the throttle a jab. All sounds good. Clutch out, still missing. This took place over about 10 seconds and then the problem disappeared and I did another 20 miles or so to finish my journey without it happening again. Spark plugs? Coil packs? Something more sinister? Cheers Andy __________________ --- 2003 MG ZT 190 in Trophy Blue

6th April 2018, 12:47	#2
trikey Premium Trader Rover 75 Join Date: Nov 2010 Location: Devon Posts: 33,834 Thanks: 8,837 Thanked 14,831 Times in 8,030 Posts	Have you had the belts replaced recently __________________ Lest we forget..

6th April 2018, 12:50	#3
AndyJacobs Regular poster MG ZT 190 Join Date: May 2013 Location: Andover Posts: 73 Thanks: 14 Thanked 5 Times in 4 Posts	Nope. But I'm going to soon. Are you saying that the belts might need replacing? Or that the problem could be caused by having the belts replaced? I found a local place that seemed to specialise in MGs. I gave them the car to have the belts done and get it through the MoT. They got it through the MoT but I think they got nervous about changing the belts. I e-mailed another place on Tuesday but haven't heard back. I'm just trying to find somewhere local (ish) before I go further afield. __________________ --- 2003 MG ZT 190 in Trophy Blue

6th April 2018, 14:24	#4
trikey Premium Trader Rover 75 Join Date: Nov 2010 Location: Devon Posts: 33,834 Thanks: 8,837 Thanked 14,831 Times in 8,030 Posts	I ha e seen a few where the belts have been done and the small black earth wire has been left unattached from the rear bank, this tends to make the ecu a very unhappy boy!! __________________ Lest we forget..