Df225 driven gear then 3-2 code

[Follybob]

Hi everybody! I replaced the driven gear on my 07 df225. Marked all cam and chain positions. Loosened tensioner and removed oil pump. Replaced gear and holder. Rotated engine and marks were good. Reassembled. Motor started immediately and ran fine then threw a 3-2 code. Swapped map sensor from good motor no change. Unplugged map sensor and it threw another code so I'm assuming the harness is good. Swapped iac from good motor no change. Swapped ecu from good motor. No change. 12v power is solid double checked connections. I unplugged each spark plug and they all caused a decrease in rpm. I am at a loss for where to go next. Would someone please help me go through this and figure it out? I am struggling so much

[catacom225]

Hi Bob, What I'm suggesting will probably go against what most professionals would suggest, but I had the exact scenario with my first 140.Tested Map, replaced IAC, still had an error code. Went through the idle adjustment sequence, restarted it and error vanished. Still has me baffled! what have you to lose?

[redlowrey]

Hi everybody! I replaced the driven gear on my 07 df225. Marked all cam and chain positions. Loosened tensioner and removed oil pump. Replaced gear and holder. Rotated engine and marks were good. Reassembled. Motor started immediately and ran fine then threw a 3-2 code. Swapped map sensor from good motor no change. Unplugged map sensor and it threw another code so I'm assuming the harness is good. Swapped iac from good motor no change. Swapped ecu from good motor. No change. 12v power is solid double checked connections. I unplugged each spark plug and they all caused a decrease in rpm. I am at a loss for where to go next. Would someone please help me go through this and figure it out? I am struggling so much

''''''''''''What that code means, the ecu is not receiving a changing signal voltage on the map sensor, no matter what the engine load is. Remove the map sensor and make sure the little hole in the manifold is not blocked, also if you connect a digital multimeter on the white signal wire on the map sensor, run the engine and watch the voltage at idle, it should be just over one volt and as you rev the engine up and down it should change between one and four volts. If your valve timing is late, the map signal voltage will be high at idle.

[Follybob]

First of all thank you so much for sharing your knowledge.

Ok so I checked map voltage was 2.4 at idle. Pulled powerhead (again) and began to look around. The match marks on the block were aligned with the sprocket single dots on port and starboard intake and exhaust. I noticed the mark on the crankshaft gear was not at the 12 o'clock position and was about three teeth off. I eased the tensioner and rotated the crank gear and driven gear until they matched and were at the 12 o'clock position. I then reinstalled tensioner without disturbing the alignment.

1. If all the mark on the sprockets match their marks on the block and the crank is at 12 o'clock with tensioner installed then I am good right?

2. Is this motor an interference motor? How bad can I damage it if I am incorrect?

3. Is there a way to positively conclude that the valve timing is correct by finding tdc such as one might with an automobile engine? The manual does not cover this.

Thanks again for your help!

[redlowrey]

If all the marks and sprockets and chains line up you should be right, just have a look and make sure no 1 piston is at tdc, and there is clearance on all four valves. You will damage the valves if you are too far out of timing. Rotate the engine a few times by hand no plugs, and watch when number one comes up on overlap, you will see the inlet valves opening just before tdc and the exhaust valves closing just after tdc.

Remember ounce you rotate the engine a few times it will take about 28 turns before all the marks will line up in the right place again, that why it is important you get it right first up.

Any engine that uses a map sensor, the moment a mechanical or electrical problem occurs it will effect manifold vacuum, which in turn will effect map sensor signal voltage, eg late valve timing low manifold vacuum high map sensor voltage, same thing with a cylinder miss, tight tappets and so on.

[Follybob]

Thank you so much. So if there's no interference hand turning should be good right?

[redlowrey]

No you can be one, or maybe two teeth out before a piston will strike a valve, if you have no 1 at tdc and all the coloured chain links on all the dots you should be right, as I said on over lap you will see the inlet valves open just before tdc and the exhaust valves closing just after tdc.

[Follybob]

Hey thanks for the guidance. Got it all back together and took it out this waving. It runs great. It's tricky how the cams spin when you take the chain tensioner off. Lined up all marks verified tdc and its good. Much appreciation on the diagnostics and advice.