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Help needed please!! Missfire, rough idle, now wont start

Hi, can anyone help me please....

Just put my zed back on the road and it died the next day!!

It all started a year ago when I went over a speed hump too quick (accidentally by the way) I hit the speed hump at about 30 while braking hard and my zed instantly started running very rough, massively underpowered and holding back so I thought I must have knocked a hose off or damaged an intercooler maybe, but I looked everywhere and could find nothing. The next day the car wouldn't start so was left on the drive till now when I finally decided to get this car sorted and do some stuff to it. The car started no problem and seemed to be running fine, but I noticed a very slight misfire or something and I knew there was still an issue somewhere, the idle started to run up and down and was close to stalling... Next day it wouldn't start. I got hold of a secondhand ptu and changed it, then it started but still running a bit rough, turned it off then next time it wouldn't start again. One thing I noticed was the fuel pump in the tank sounded quite loud.

Any ideas anyone??

Sorry for the long story lol :)

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  • Author

Update on problem... Fuel is definitely getting to the plugs turned out it was flooded and I used a handy tip from the forum to remove the fuel pump fuse and turn over a few times then replace it and got a loud bang out the exhaust but didn't quite start to removed plugs span it over and dried the plugs and bingo it started but still running rough... Feels like its running on 5 cylinders or something, and won't be surprised if it don't start in the morning :(

I would say that the first thing to do is estabilish that you have a spark at the plug. Once you are happy that all 6 are firing and you defo have fuel, listen to the injectors and ensure that all are clicking away. If all is well, check all electrical plugs for corrosion and give them a good clean and re-seat them (make sure they are positively engaged). If the car has been sitting for a while this could be the problem. Check all hoses for psible vacuum leaks.

do a boost leak test, i think you may find youve knocked off an intercooler hose partially or cracked one. the hoses for the fuel are also down there but its more likely the front youve given a whack just go over and inspect it all.

  • Author

Thanks guys I'm gonna have another look tonight and go over all the connections giving them a good clean making sure they all are nice and tight and good contact, will also check all 6 are firing by unplugging the coils 1 at a time. Never checked injectors before but I'll have a listen to them. Will also double check inter coolers again and pipes.... What's the best way of checking for air/boost leaks?

Thanks

  • Author

I'm a happy zed owner again :) managed to locate the prob which was it was only running on 4 cylinders due to corrosion on 2 of the injector connections! Now gonna think about changing the loom but not sure how big a job that is yet, it looks quite a challenge

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