Very Strange Engine/Exhaust Problem

[M. Nader]

Hello everyone,

I think i am now technically half dead so i will try to keep this brief just so that i can get some sleep.

We are using the Honda CBR600RR 2008 California edition engine with the Performance Electronics Edge ECU (PE3).

We have started the engine using the stock ECU with no problems, and with the PE ECU, We have added in our intake system and started the engine with no problem, We have used the stock Exhaust as the one we manufactured had some critical errors which prevented us from using it and we decided the stock exhaust would be the faster solution.
Till now the engine, with the intake, stock exhaust and ECU have been running with no problems, up to today.

Yesterday While filling in the fuel tank some fuel splashed on the Harness which short circuited it and we had to disassemble it and trace it, we did that and fixed it and started the engine today after several attempts.

after starting the engine we noticed some smoke coming out from the exhaust so we turned it off and started it again, same problem and also the exhaust tubes coming from cylinders 1 and 2 are way too hot (near getting red hot) after no more than a minute of operation while the exhaust tubes from cylinders 3 and 4 are very cool that we can wrap our hands around them. The smoke is also appearing from exhaust tubes from cylinders 1 and 2 and not 3 and 4. Another noticeable feature was that the engine RPM and noise changed radically after starting it and the RPM reached nearly 4500RPM (idle at 2000 normally) with no one operating the throttle, We fixed that by lowering the air/Fuel ratio from the ECU and everything was back to normal except for the smoke and exhaust tube temperatures of cylinders 1 and 2.

We have checked the injectors' signal and all seem to be working, spark plug signals are also working, We even swapped the spark plugs between cylinders 1,2 and 3,4 and cylinders 1 and 2 still produced smoke and their exhaust tubes are flaming hot. We disassembled the exhaust from the engine and everything looks good on it, but the ports from cylinders 1 and 2 are very dry and ports 3 and 4 have some fuel in them.

Another clue is that the water temperature was changing quite quickly in comparison to our previous runs, and even after turning off the engine the water temperature increases by nearly 10 degrees F before starting to cool down.

We have tested nearly everything from the electronics side and everything we looked at is OK, We checked the spark plugs and injectors and they are OK as well.

We are now officially out of ideas and the only thing left for us is to disassemble the cylinder head and check if anything is wrong inside. We reckon the problem is not Cylinders 3 and 4 being cool but more cylinders 1 and 2 getting way hotter than they should be (in nearly a 30 seconds operation you would expect the exhaust tubes to be cool enough to touch), We suspect that maybe something is broken inside the engine (or maybe even a piece of plastic slipped in while we were assembling the intake or something) or the engine was hit while we were transferring it from the lab and a gasket is shifted from place. We really are guessing here as everything tested is working well. I personally suspect that cylinders 1 and 2 may not be getting enough fuel from the injectors and i am thinking of having another look at them but all seems to be well.

The only thing that we have changed from our previous times was the bolt in the water drain on the cylinder side and i think we replaced it with a longer bolt which we suspect is blocking the coolant flow to cylinders 1 and 2 which would explain the smoke and exhaust tubes over heating.


Anyone has any guesses as to what may be the problem or has anyone ran into a similar situation?



That was not brief i guess

[M. Nader]

Hello everyone,

I think i am now technically half dead so i will try to keep this brief just so that i can get some sleep.

We are using the Honda CBR600RR 2008 California edition engine with the Performance Electronics Edge ECU (PE3).

We have started the engine using the stock ECU with no problems, and with the PE ECU, We have added in our intake system and started the engine with no problem, We have used the stock Exhaust as the one we manufactured had some critical errors which prevented us from using it and we decided the stock exhaust would be the faster solution.
Till now the engine, with the intake, stock exhaust and ECU have been running with no problems, up to today.

Yesterday While filling in the fuel tank some fuel splashed on the Harness which short circuited it and we had to disassemble it and trace it, we did that and fixed it and started the engine today after several attempts.

after starting the engine we noticed some smoke coming out from the exhaust so we turned it off and started it again, same problem and also the exhaust tubes coming from cylinders 1 and 2 are way too hot (near getting red hot) after no more than a minute of operation while the exhaust tubes from cylinders 3 and 4 are very cool that we can wrap our hands around them. The smoke is also appearing from exhaust tubes from cylinders 1 and 2 and not 3 and 4. Another noticeable feature was that the engine RPM and noise changed radically after starting it and the RPM reached nearly 4500RPM (idle at 2000 normally) with no one operating the throttle, We fixed that by lowering the air/Fuel ratio from the ECU and everything was back to normal except for the smoke and exhaust tube temperatures of cylinders 1 and 2.

We have checked the injectors' signal and all seem to be working, spark plug signals are also working, We even swapped the spark plugs between cylinders 1,2 and 3,4 and cylinders 1 and 2 still produced smoke and their exhaust tubes are flaming hot. We disassembled the exhaust from the engine and everything looks good on it, but the ports from cylinders 1 and 2 are very dry and ports 3 and 4 have some fuel in them.

Another clue is that the water temperature was changing quite quickly in comparison to our previous runs, and even after turning off the engine the water temperature increases by nearly 10 degrees F before starting to cool down.

We have tested nearly everything from the electronics side and everything we looked at is OK, We checked the spark plugs and injectors and they are OK as well.

We are now officially out of ideas and the only thing left for us is to disassemble the cylinder head and check if anything is wrong inside. We reckon the problem is not Cylinders 3 and 4 being cool but more cylinders 1 and 2 getting way hotter than they should be (in nearly a 30 seconds operation you would expect the exhaust tubes to be cool enough to touch), We suspect that maybe something is broken inside the engine (or maybe even a piece of plastic slipped in while we were assembling the intake or something) or the engine was hit while we were transferring it from the lab and a gasket is shifted from place. We really are guessing here as everything tested is working well. I personally suspect that cylinders 1 and 2 may not be getting enough fuel from the injectors and i am thinking of having another look at them but all seems to be well.

The only thing that we have changed from our previous times was the bolt in the water drain on the cylinder side and i think we replaced it with a longer bolt which we suspect is blocking the coolant flow to cylinders 1 and 2 which would explain the smoke and exhaust tubes over heating.


Anyone has any guesses as to what may be the problem or has anyone ran into a similar situation?



That was not brief i guess

[Drew Price]

Did you check the compression? Do that before you pull the head off - if the compression is fine there's no reason to pull the head yet.

Only thing that could have gone wrong if you dropped something down the intake on re-assembly is a valve may have closed on it and is either bent, or being held partially open, you'll see no compression on those cylinders if that happened. (It could also have gotten chewed up and messed up the piston, but you'd hear it if something horrible happened mechanically to make you think that).

Do you still have the harness and stock ECU to install and see if it shorted the injector drivers in the PE3 or something like that?

You said you tested the injector outputs, how did you do that?

[Warpspeed]

I agree, a compression check should reveal anything basically mechanically wrong with the valves, valve train, or head gasket.

There is something very suspicious about the 1,4 2,3 relationship which makes me think a couple of plug leads may have been swapped over on the cold cylinders.

[M. Nader]

@DREW
We have not yet done a compression test, i guess we will do that first thing tomorrow.

We still have the stock ECU, but i think the PE ECU is fine but we are desperate so maybe we will give it a shot but only after ruling out everything.
We tested the injectors by giving every single one of them signals from the ECU and we heard each one of them click as the signal was give, we did not physically see the fuel go out but the signal is there we are sure of that.


@Tony We are also baffled as to why two cylinders next to each others would do that (1 and 2 being hot, 3 and 4 being cold). even after swapping the spark plugs the same two cylinders were getting hotter

[Wesley]

What's your plenum design look like? Sounds like either:

-You have a vaccum leak on cyl 1-2 and it's leaning out.

-You have a vaccuum leak in cyl 3-4 and you've now leaned it out so much they aren't firing, while 1-2 are getting air from the leak and running even leaner. Remember, a misfiring cylinder looks like a rich condition on a WBO2

What do the spark plugs look like?

Also, how did spilling fuel short circuit your harness? Fuel (at least gasoline) is non-conductive.

[B Lewis @ PE Engine Management]

Hi Guys,

First things first. If then engine wants to idle at 4500 RPM you have large vacuum leak somewhere. You should never adjust the idle speed by changing the mixture as this results in either fouling plugs or sluggish off-idle performance. Before you do anything you have to fix the vacuum leak and adjust the idle down by restricting air not by leaning it out. You should strive to give the engine the amount of fuel that it wants at idle to produce the best torque. This means to set the idle stop and then set the idle fueling so that the engine runs the fastest RPM for that throttle setting and then closing the throttle with the idle stop. This is an iterative process.

Also, if you can wrap your hands around the exhaust tube while the engine is idling for more that a few seconds, that cylinder is not firing at all. I would also try to rule out fouled plugs by torching them with a propane torch or installing new ones.

[M. Nader]

Just to update:

<UL TYPE=SQUARE> We removed the PE ECU and moved at it wire by wire using a potentiometer and all wires are conducting signals
We are using the same Map we used when running the engine previously and all works perfectly, in fact we used two versions of this map which we tested earlier when everything was working well, and both produce the same problem of 2 cylinders not firing.
We replaced our Intake system with the stock air box, no change[/list]
The only things left for us is to triple check the wiring and ECU again and the compression test, any ideas?


We are more inclined to an ECU problem now, as when we opened the ports, put our hand on them and started the engine we could feel suction from all cylinders.

[M. Nader]

Now the engine won't even start.

We took the spark plugs off, gave a signal to each one of them separately and saw the spark from every single one. However when we took them all of simultaneously and connected the engine (as in starting it) non of them gave a spark!

[Warpspeed]

Sounds like a case of putting the stock ECU back in. Probably nothing wrong with the engine itself.

In a way it is probably a good thing that you now have a definite failure.
Nothing worse than hard to trace intermittent problems that go away and come back later, always at the most inconvenient times.