Engine Help!! Cylinder #4 is dead.

[Luis_85]

We are having problems with our engine (GSXR 600 -2005),the cylinder #4 is not making the combustion properly,the last days we started to tuning up our engine (working with our fuel and advance maps) and the first day we noticed that this cylinder was not working well,we realiazed this because the header (configuration 4-2-1) was hot and red only on the the rest of the cylinders,number four was cold and it seems dead to us,at this moment we try to figure out the problem (coil,spark plug,injector,the conectors,compresion in the cylinder,etc,etc) and we found nothing wrong; rigth now we are clueless about what to do and the reason of the failure. Next is the list of things we had done in order to figure out our problem.

1. Injectors.
We checked if the injectors were working,we can send a pulse with our ECU (PE) and see if they are spraying or not, they did; we checked the voltage on the conectors (was ok);and finally we swap injector #1 with injector #4 in order to see if injector #4 was in some level damage causing to spray less fuel than the others (wasn't the case,cylinder #4 was still failing after the swap). After all this the problem was still present.

2. Coils
We did the same as the injectors,we checked the voltage on the conectors (was ok),cheked is they were working (sending the pulse from the ecu and verifying that the sparks where working),they were, and finally we swap coil #1 with #4,after all this we still had the problem.

3.Spark plugs.
We checked if the spark plug were working (they were);swap #1 with #4 (the problem persisted) and we even putted a brand new pair and did all again and no improvement was seem.

4. Mechanical
We checked compresion on cylinder #4, we got a value of 130 that is aceptable,then we test for losses inside the cylinder and we obtain only 1%,so the cylinder is seal,we can say that the train valve is sealing and working well.

5. Electrical
As i said we check all the conectors and they were working fine.

6. Admision System.
In one moment we thougth that maybe our intake system was not delivering the rigth amount of air to the cylinder (maybe too much or too less), so we inverse the position of it (our air intake faces the front of the car,we putted it facing to the back) and we saw no difference,four was still having the problem and #1 was working fine.

7. Header
Finally we thougth that maybe the reason of the failure could be our header, the primary length of cylinder #4 is shorter than the rest of the cylinders,so we remove it and it was the same behavior; the only thing we realized at that moment was that the cylinder was making the combustion but not at the same pace as the others,it looked like it was in other frequency.

We also make changes on our fuel & advances maps to check that this was the reason and nothing,and we also swap all the components (coil,spark plug,injectors) between #1 and #4 and nothing happened.

I really dont know what to do next,and as i said i'm clueless. So please any help you can give me is more than welcome.

We really apreciate your help.

Thanks in advance

Regards

[Luis_85]

We are having problems with our engine (GSXR 600 -2005),the cylinder #4 is not making the combustion properly,the last days we started to tuning up our engine (working with our fuel and advance maps) and the first day we noticed that this cylinder was not working well,we realiazed this because the header (configuration 4-2-1) was hot and red only on the the rest of the cylinders,number four was cold and it seems dead to us,at this moment we try to figure out the problem (coil,spark plug,injector,the conectors,compresion in the cylinder,etc,etc) and we found nothing wrong; rigth now we are clueless about what to do and the reason of the failure. Next is the list of things we had done in order to figure out our problem.

1. Injectors.
We checked if the injectors were working,we can send a pulse with our ECU (PE) and see if they are spraying or not, they did; we checked the voltage on the conectors (was ok);and finally we swap injector #1 with injector #4 in order to see if injector #4 was in some level damage causing to spray less fuel than the others (wasn't the case,cylinder #4 was still failing after the swap). After all this the problem was still present.

2. Coils
We did the same as the injectors,we checked the voltage on the conectors (was ok),cheked is they were working (sending the pulse from the ecu and verifying that the sparks where working),they were, and finally we swap coil #1 with #4,after all this we still had the problem.

3.Spark plugs.
We checked if the spark plug were working (they were);swap #1 with #4 (the problem persisted) and we even putted a brand new pair and did all again and no improvement was seem.

4. Mechanical
We checked compresion on cylinder #4, we got a value of 130 that is aceptable,then we test for losses inside the cylinder and we obtain only 1%,so the cylinder is seal,we can say that the train valve is sealing and working well.

5. Electrical
As i said we check all the conectors and they were working fine.

6. Admision System.
In one moment we thougth that maybe our intake system was not delivering the rigth amount of air to the cylinder (maybe too much or too less), so we inverse the position of it (our air intake faces the front of the car,we putted it facing to the back) and we saw no difference,four was still having the problem and #1 was working fine.

7. Header
Finally we thougth that maybe the reason of the failure could be our header, the primary length of cylinder #4 is shorter than the rest of the cylinders,so we remove it and it was the same behavior; the only thing we realized at that moment was that the cylinder was making the combustion but not at the same pace as the others,it looked like it was in other frequency.

We also make changes on our fuel & advances maps to check that this was the reason and nothing,and we also swap all the components (coil,spark plug,injectors) between #1 and #4 and nothing happened.

I really dont know what to do next,and as i said i'm clueless. So please any help you can give me is more than welcome.

We really apreciate your help.

Thanks in advance

Regards

[The Bunker]

With the PE, there is a cylinder compensation.....is this accidently set at a low value or zero?

Also, what did the plug look like when pulled out of the #4 cylinder...wet, dry, full of soot, white??

Also, are you tuning on an engine dyno, or just in the car?

Sounds like you guys have done a good job of trying to track the problem....it sure is frustrating when these type of problems come up!

[HenningO]

If they swapped the coils and injectors between 1 and 4, it shouldn't be the cylinder compensation.

Is #4 pumping any air when you are cranking? (crank without intake, hold hand over port) Maybe a stupid question, but since you've gone through everything else? You said you had compression, maybe the valves aren't opening? Once again, long shot...

[The Gus]

One of my favourite tests is to switch the electrical connector from one cylinder to another - in addition to switching the injector or coil itself. Since it's the PE (and you're forced to run batch injection and wasted spark) you can switch connectors for cylinders 1 with 4.

[Pete M]

Just a quick sanity check, what does it sound like when running? Does it sound extremely rough or did it sound like it was running on all 4 cylinders? If it still sounded smooth you've still got all 4 even if some imbalance is making one of the headers not glow.

[mike86z28]

any EGT's?

Does cylinder 4 fire at all, or it is cold. By cold, I mean you can touch it by hand.

Could be a valve issue, I hope not.

[Kirby]

Could be a valve issue, but its a direct actuation but tappets. So your valve issues are limited to twisted cam or a missing lobe?!?!

The compression test kind of negates this however.

[Luis_85]

Hi everyone,thank you for posting.

To bunker: the cylinder compensation is not set on a lower value or zero,is set at 115% (bank #2 is referenced to bank #1), we are tunnin in the car and the plug is dry, also when you remove the intake and see inside the port you can see the valves wet in fuel.

To HenningO: yes the cylnder is pumping air,we try that experiment and it was puming like the rest of the cylinders. And in the case that the valves aren't opening properly,how we can check this?

To The Gus: we also did that we switch the conectors from cylinder #1 and #4 on the injectors and coils.

Te engine sounds clean it doesnt have a rough sound per se,but the cylinder four is not doing practically nothing to the engine, when the engine is working we remove the conector from the injector and coil of this cylinder and we didn't receive any feeling of the engine dropping power,this case happen when we did this test whith the rest of the cylinders.

To mike86z28: the cylinder firing,we noticed this when we remove the header (when the header was in position the cylinder was cold,we can touch it with our hands)and how it could be a valve issue,i have compresion and sealing,that doesnt mean that the valve are ok? valve timing is ok, because then engine sounds neat, and ignition timing is ok, because cylinder 1 is working properly (PE works with wasted spark, cylinders 1 and 4 fires at the same time)

[JamesCH13]

Have you taken the spark plug and coil out, grounded them to the frame, and watched it spark while the car is running? The ECU might not be triggering the spark properly.

Have you verified that the injector is receiving a signal? If it has been dumping fuel into the cylinder and cycling it though you'd be getting huge backfires (our CBR kicked 2 cylinders last year and backfires sounded like gunshots, they actually shifted the whole exhaust header).

I would try getting an analog o-scope and connecting it to cylinders' 3 and 4 ignition and injectors to see if they're getting the same signal. The scope should be old-school analog, they're much better at picking up the scattered waveforms you'll be dealing with.

Also, what ECU are you using?

[Kirby]

Do you have twin-post coils and leads?
or are you running Coil-on-Plugs?

Could you get a scope on your injectors and compare the signals between #1,#2,#3 and #4?

Once again, there isn't any wierd config in your ECU like staged injection turned on for #4 or something?

With what you have said, this one has got me scratching my head.

[billyredline]

You have done the power balance, you checked compression, timings on the money, and from what I thought I read you have fuel delivery. Kirby has the best idea of hooking up a scope and looking at the readings. You have spark, compression, and fuel, which is all that you need to start any motorcycle engine or car engine. It sounds like you guys did something wrong during tuning.

Now this procedure will get criticism from everyone which is good, and it does take caution. It is done with automotive engines when questions need to be answered, and I have only seen it done to a couple old English bikes at the engine rebuilding shop I work at. I am sure that this will get a number of responses which is great for you because there are a great deal of people here that deal with GSXR engines, and can tell you to think about it. Try injecting A LITTLE propane into the dead cylinder and seeing if it fires. The Key word is A LITTLE, I will write it again A LITTLE, you also need good ears to listen for any change. If it fires you have spark, if it does not then you don't.

Legal note:
This procedure is done to automotive engines; has been seen done to 2 motor cycle engines, with no destruction. This write does not condone playing with fire, propane, guns, engines, or race cars. You must be 18 years or older to play, void were prohibited. Please consult a physician if rash and burning continues.

[Michael Hart]

You mentioned that compression for cylinder 4 is 130...what were the other cylinders? If they are dramatically different, that could be indicative of a problem

also, have you checked the valve clearances? To be honest, I think that there's a good chance that those might be off - if they are, the the valves would be sealing just fine (giving good leakdown numbers) but not opening properly when the engine is running (keeping fuel out of the cylinder and causing fuel to build up on the backside of the valves). It's not too hard to check, but it can be something easy to overlook.

[Grant Mahler]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by billyredline:
Now this procedure will get criticism from everyone which is good, and it does take caution. It is done with automotive engines when questions need to be answered, and I have only seen it done to a couple old English bikes at the engine rebuilding shop I work at. I am sure that this will get a number of responses which is great for you because there are a great deal of people here that deal with GSXR engines, and can tell you to think about it. Try injecting A LITTLE propane into the dead cylinder and seeing if it fires. The Key word is A LITTLE, I will write it again A LITTLE, you also need good ears to listen for any change. If it fires you have spark, if it does not then you don't.

</div></BLOCKQUOTE>

haha.

hahahahhahahahahahhahaahhaha.

hahah.

heh.

[jpusb]

Luis,

The first thing I'd do is check compression with another gauge (not the one you just used), on 4 cyls. Have that number written down and check your Suzuki manual for what it should be reading. 130 seems a little low to me but I'm not sure about Suzuki.

The 2nd thing I'd do is check valve timing. Be sure to have your camshafts aligned and right where they need to be. Your Suzuki manual should tell you that, and also valve lift and duration. Get a dial indicator and check that so you are sure you don't have a twisted cam (never seen that before). Do that of course after checking valve lash and be sure to check it right. You could also change your camshafts for the ones in another motor you have there in your shop.

The 3rd thing I'd do is check the wiring harness. Believe me that gives long sleepless night. Be sure not to have a short circuit or not to have a ground where there needs to be one. Be sure not to have ANY wire near the header, around and specially above it. BE SURE not to have 2 wires melted into one for this. By the way you said you've checked coils, sparks, and injectors so far this could be passing throuhg those checks and still be the problem, 'cause you check one at a time and not all working together in a specific order. A short circuit in the coil harness (that maybe you don't see now 'cause it made contact for just a moment) could have (almost sure it did if it made contact) damaged a component in your PE, the one corresponding to coil fire on 4 cyl. engines. Be sure to have the PE checked by your electronics guys.
The 4th thing I'd do is have a beer and relax, Solera verde so you be sure it gets to you, because this problems always end up being some dumb stuff you just let pass not intentionally, everybody has gone through something like this at least once.

Anything else you need, any questions or if you want any another info. about these 4 cyl. problems in the land of impossible things to happen, Venezuela, just let me know, juanp.fsaeusb@gmail.com

Juan P. Viera
F-SAE USB Engine Leader

[Davidimurray]

We had a not dissimilar problem a couple of years ago with an F4i. One cylinder was running 'cold' based on exhaust colour. Tried lots of things to diagnose the problem, but the engine then went and bent a valve, so we assumed that this was the cause. Setup another engine and had exactly the same problem. It turned out that the original throttle bodies we had sealed up with some chemical metal a few years prior had lost a bit of the chemical metal, Leaving a hole into one inlet runner where that couldn't be easily seen. As you may have now guessed, the bit of chemical metal must have come loose, flown round a bit, and then found itself between a valve and piston in the first engine!

[fart can]

I agree with Michael Hart-- you really need to check your valve clearances. Although the service intervals for most japanese motors are about 20,000 miles, you should check-- especially if you've never checked the clearances before. It's not too hard, usually stuff is just in the way.

Otherwise you may end up with something like Davidmurray mentioned...bent valves.

In the end it will probably be something silly with your PE settings or wiring, but you should really check your valve clearances.

[Nitesh]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by JamesCH13:
Have you taken the spark plug and coil out, grounded them to the frame, and watched it spark while the car is running? The ECU might not be triggering the spark properly.

Also, what ECU are you using? </div></BLOCKQUOTE>

I second that one. we had a similar problem with our R6 running on a PE. When we tested for the spark by sending the pulses, they were working. But when we checked it using the above method, turned out that the spark plug wasn't firing! Turned out to be a result of a loose connection.

Another one.. Might be a little off, but is there a blockage in your fuel rail that's not allowing enough fuel pressure at the 4th cylinder. Is the spray from the 4th injector same as the others? Or you can try turning your fuel rail around if possible to mount it the other way.

..just my two cents

[exFSAE]

Ok. It's either not getting fuel, not getting air, or not getting spark.. or not getting them at the right time.

O-scope everything, make sure fuel and spark are triggering at the right times.

[B Lewis @ PE Engine Management]

Luis_85,

I just ran across your post. Did you get your problem resolved?

Regards,

[Luis_85]

Hi to everyone again,thank you for your help.

We fixed the problem with our engine 2 weeks ago,i hadn't been able to post for FSAE reason (hard work no time for myself jejejeje); the problem was a crack exhaust valve,one of the slash caps of the exhaust valve slide out of his position and the valve crack a little bit on the top,that was the issue. We figured this out when we checked the valve clearence (following the suggestion you gave us). We bougth a new exhaust valve,installed it and tested the engine again,the compresion are ok, and the four cylinders are workin nice.

Again thanks everyone,and hopefully see you all on May = )

[The AFX Master]

Nice to hear that guys http://fsae.com/groupee_common/emoticons/icon_biggrin.gif!!

How are you going with your car? seems to be that you're almost as full of works as us.

[B Lewis @ PE Engine Management]

That's great!

Glad to see you are back up and running. See you in Detroit.