Hesitation and misfires

[Joan Nuevo]

Hi there, new to the forum. I just bought a Seat Leon mk2 fr and I'm already having issues. Obd2 throws a misfire on cylinder 2. Changed sparkplugs and coils, still there. I had a stuck open thermostat, changed that and hesitations reduced by 70%, but obd2 still throws a misfire on cylinder 2. Mechanic said it could be an injector or a bad cylinder valve. I would like to check the injectors myself, but I can't find where the hell they are. Any help / opinions? I'll have to do a compression test, but I'm afraid... Thanks!

UPDATE: I just checked my obd2 and there's no more misfire code, now is a "lean code on bank 1". I'll try to get a smoke test. Any ideas?

 

[mty12345]

Hi there, new to the forum. I just bought a Seat Leon mk2 fr and I'm already having issues. Obd2 throws a misfire on cylinder 2. Changed sparkplugs and coils, still there. I had a stuck open thermostat, changed that and hesitations reduced by 70%, but obd2 still throws a misfire on cylinder 2. Mechanic said it could be an injector or a bad cylinder valve. I would like to check the injectors myself, but I can't find where the hell they are. Any help / opinions? I'll have to do a compression test, but I'm afraid... Thanks!

UPDATE: I just checked my obd2 and there's no more misfire code, now is a "lean code on bank 1". I'll try to get a smoke test. Any ideas?

The injectors inject straight into the cylinders rather than the inlet manifold on these engines.

Most likely a vacuum leak somewhere. Smoke test will probably reveal it, but if you can't get a smoke test then the old fasioned way is to spray a small amount of 'easy start' or brake cleaner around the pipework. When the idle speed increases, it means the easy start is being sucked in through a leak in that area.

 

[Leeoncupra]

Bank1 is the pre cat o2 sensor

Pcv valve can cause misfires and hesitation on the 2.0 tfsi

A quick test is to slacken off the oil fill cap whilst idling and see if the engine noticeably starts hunting and resolves itself once tightened back up

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[Joan Nuevo]

Bank1 is the pre cat o2 sensor

Pcv valve can cause misfires and hesitation on the 2.0 tfsi

A quick test is to slacken off the oil fill cap whilst idling and see if the engine noticeably starts hunting and resolves itself once tightened back up

Sent from my SM-G950F using Tapatalk

Okay, I'll try that up. Is there any "common" problems with this engine? I'll try to have a smoke test done this week (it has been Easter so all shops where closed). If I try that, what should I assume? Vacuum leak?

 

[Joan Nuevo]

Okay, so the mechanic took a look and said that the pressure hose from the turbo was disconnected. He connected it back and now runs much smoother, but not good. I feel a loss in power and acceleration and still on my obd2 I can see that the fuel trims are off the roof. He also did a compression test and everything looked good. I noticed a clicking sound coming from the fuse box under the drivers dash. The sound comes when I am driving only. Any idea? Fuel pump relay maybe?

 

[Leeoncupra]

What fault codes are stored on the ecu?

Surely it may have logged something to give you a basis to go from matey

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