Wuts up guys I have been lurking through honda tech for awhile, I have a problem with my eg with a k20z1, I'll try to explain everything that happened and what I have checked so far.

A week ago I decided to add 5 degrees of vtc, made a quick pull and noticed an increase in power right away, so I left it alone with 45 degrees max vtc. Later that night I made another pull and was all in it 3rd, 4th, 5th, and while in 6th gear in vtec roughly 6500 rpm, the car bogged and lost power. I slowed down and checked to see if I broke something, I saw nothing out of the ordinary. Oil level was good and there were no abnormal noises. I made another 3rd gear pull and it pulls strong on low cam but once vtec is suppose to hit it bogs. It sounds as if vtec lobes are not activating, low cam giving it all it has. When it hits vtec crossover it gets rich, I had the tune at 13.1 at wot, and now once in vtec goes 10.1 afr.
So I checked the vtec solenoid, the screen was clean and replaced the solenoid with one I knew that worked just to see if it would do anything. Also checked my tps voltage, right now its .8v closed and 4.9v wot. I datalogged a pass I did and nothing seemed out of the ordinary. Also took off my valve cover, didn't see any metal shaving or nothing abnormal. I also changed my oil filter thinking it might be oil pressure related. Then someone told me to check my grounds, I did and I found one loose and I tightened it. I also added another ground just to add one.

When I am cruising and slowly go into vtec I can hear the crossover, it drives perfect on low cam. Because I did find a ground loose maybe I fried a sensor, map sensor maybe, or ecu, I don't know.

Just wanted your guys input, maybe you will come up with something I haven't . The things I will do are get an oil pressure gauge and see wut the psi is at, and recheck the harness for anything that's stands out.

If you need more info let me know

 

are you running kpro or ems?

 

I am running kpro, I can still upload and datalog. I thought maybe my tune messed up somehow so I put in a stock map. Still sounds the same, runs great on partial throttle. Just once vtec supposed to kick in sounds like primary lobe is giving all its got. I tuned out when it goes rich and now afr's are 13.1 all across. But still not pulling like it used to.

Going to buy a oil pressure gauge after work, I kinda think I have an oil pressure problem.

I also checked my timing chain thinking maybe it jumped, but everything is still on time.

 

Alright I just checked oil pressure, 30 psi at idle while I'm cruising it goes to 80 psi, wot stays at 80 psi then around 4500 where vtec is set it goes 100 psi.

Since oil pressure is good, then I don't have an oil psi problem, in kpro cam command and actual cam angle are right behind each other. I still don't throw a c.e.l. not for cam angle being bad nor vtec oil pressure switch.

Since I did find that loose ground I'm thinking the map sensor shorted itself out. But on the datalong at wot it reads -.4 psi at 8 to 9 column. The only 2 things that come to mind that would make afrs change are tps and map. It uses those 2 things to scence a load. I have had the map sensor go bad a couple months ago but the car wouldn't start. I crossed the plugs for tps and map but I engraved wut each one is since then. From wut I know when the tps goes bad the car would jerk and not be smooth, but I don't have that problem. I'm still driving the car, but without full potential of the motor its not as fun.

Now I'm thinking tps or map sensor or both are bad.

 

I figured I would keep you guys updated on my hunt for vtec. After chasing wut people have told me "bad ground" I did not find such a thing. I even redid my conversion harness, looks presentable now. Its not my wiring or electrical problem.

I put a test light to the vtec solenoid ecu pin out, when I'm in vtec the test light lit up, I then ran I wire to the solenoid in engine bay and it also lit up when vtec engaged. Then I took out the vtec oil pressure switch and hooked up my gauge to it. Cruising it reads 5psi or less, when vtec engages it reads constant 100 psi untill vtec disengages. So it diffently is getting oil, I think only the exhaust is activating and for some reason intake cam is not. I was trying to find out what the oil routes are to see where it goes after the solenoid but had no luck.

The local honda dealer said there's a special tool that locks the rockers into vtec with air psi, but they only had half the tool which makes it useless, in the service manual you can see the tool in action. I found out the part numbers for it but they can't order them, and can't find it on the net.

Last night I tried my jdm ep3 ecu just cuz I had it laying around, but still no vtec. So my kpro is good. I've had my valve cover off so many times just to see if something gave up, but I don't see nothing wrong with it. One thing I do see is that it looks like the cam is not tight against the cam rails and caps. But that's just by looking at it not measuring anything. When I put the motor together I did change 3 cam caps cuz they were scored, and I had a spare k24 head that I took them out from. I know they were same when I swapped them over, but maybe it changed my clearances. I've had vtec working for months before but who knows.

I don't work this weekend so I'm taking off the valvetrain to see wuts goin on.

 

hello i have a varry sim problem but k pro gives me a p0011 vtc system malf. did u have the vtc selonid tested and do u know how i can check if the comp. is putting the correct volts to the vtc. i got a diy wire tuck and i checked cont. in the wires but im not shure if they r conected to the plug correctly does it matter pos. neg. thanks

 

Well I don't have a vtc problem, I can see through kpro that the cam moves. I'm sure it does matter where the 2 wires go cuz the vtc moves one way once power gets to it. I took a pick of what mine looks like hope it helps.

 

thanks for the pic i am new to k series and i am not shure how to veiw the cam movments in kpro how do u c that

 

When you open kpro you're. Gonna hit the lightning bolt to datalog. Click on the tap for sensors and you will see all the sensoors readings.

CAMCMD= is the amount of degrees the ecu wants.

CAM= the actual cam readings

They should follow each other. Hope that helps

 

thanks again and sorry im not more help to u

 

did u pull the valve train off and find anything wrong

 

Yup, I pulled the cams and the rockers this past weekend. I found nothing wrong with them, all the pins move freely. The springs in the pins were there. I have eliminated that vtec is the problem.

I spoke to a honda technician, and after awhile of talking to him, he said I could have a stretched chain. Has anyone experienced a stretched chain? Symptoms? It does make sense if it is stretched cuz that would mean the exhast cam would be "x" amount of degrees retarded. When its going at wot intake cam advances to give it more overlap and will create more torque which is why we love"k" series. But if the exhaust cam is retarded then valve events are not happening when they should, meaning more overlap which would explain my bogging.

What I don't understand is why if it did stretch, how come I have no codes, like "timing off" or something, I figured its smart enough to tell me. Or intake cam is compensating for how much exhaust cam is off. Don't know just thinking out loud. If I have anything wrong up there let me know.

 

I have seen this on a couple motors that the valve lash was set to tight on . They run fine for awhile then started dieing when vtec hit becaue the valves are floating or stuck open a little just a idea. If it was a sensor it should show up deffently seems mechanical . Try backing off the valve lash a little . I hope you get it figured out man . Deffently sounds like the valves are not closing sll the way in vtec or something of that nature .

 

Sounds like it jumped timing..

 

Ecu would throw codes immediately. Camshaft range and tdc codes

 

I thought about that too, after the fact that i posted.. but then i realized that its not always caught.

I had a few Audi's jump their chains , because they were stretched but no signs of it, no codes neither..

Just a thought to just double check, he's tried everything else, might as well eliminate something as cam gear and crank timing..


Its also possible the chain tensioner is going out??

 

Yea I thought it could have been valve lash, so when I put the valvetrain in this past weekend I set them a little looser. While I was putting the chain on and checking timing and lined up the crank the cams were about 2mm off very minimal. I checked this while lookin at the back of the cam, which is suppose to line up with the cam cap. When I lined up the cams to the caps, the crank is about the same 2-3mm off. The only reason I thought nothing of it, cuz when I assembled the motor the first time around it was the same. The engine was very strong.

One thing I forgot to mention was yesterday I did a compression test and leak down test, to see how the motor was doing. I had 210 psi in all 4 cylinders and nothing more than 5% leak in all 4 cylinders.

I'm gonna order a new chain and tensioner to get it out of the way, I reused them and don't know the mileage on them both.

 

This is interesting...
You've checked everything I was going to suggest. Keep us posted on the problem. GL

 

I firmly believe its a chain tensioning problem.. keep us posted, i have two k customers looking at this as well.

 

I will keep you guys posted, whenever I figure it out. I have a video on what the car sounds like at wot, but my phone doesn't let me so I have to wait until I get home.

This is the only car I own besides a bike, so I can't take it apart during the week only weekends. Can't have too much down time. Also need to post the datalog from kpro, maybe you guys will see something.

 

Bad quality but in the first 15 secs. i did a 2nd gear pull. You can clearly hear the problem.

http://www.youtube.com/watch?v=qypx3DyJWQ0

 

Just replaced my timing chain and tensioner, I was feeling good when all timing marks were on point. A lot better than the other set. I just went to go make a pull and it still acts the same.........

I dont know what the hell I broke, but I know something isn't right. I can post pics that i took of the new chain and tensioner if anyone wants to see them. I have my map and datalog I just did, gonna try to post it.

 

Dont know how to attach either files I guess I can email them to you or show me how to post it...

 

hrmm.. i'm thinking..

Good compression and leakdown numbers??



You've tried another ecu.. that didn't work.

You redid your entire timing chain setup, that didn't work

Is it possible your map got corrupted from the transfer? Or that kpro just took a crap?

have you tried re uploading your map or even starting from scratch?


lets tie up some lose ends.

 

Yessir, I have put in a stock map that kpro has, I was thinking the same thing, maybe the map got corrupted, but the engine acts the same. After I did that I thought kpro got damaged, which is when I put in a jdm ep3 ecu. The car runs good besides it being lean, and it would throw codes for multiplex, eld, both o2 sensors. But still acts the same.