Hello,

I am tuning my build F23 block and H22 head hybrid.

The engine runs fine below 4700 rpm. delivery is smooth.

AFR all around is good.

Compression of the engine should be 9.8:1 - its running all motor for now, i hope to bolt on a turbo once am confident it works well.

My problem is that, as soon as i go up the RPM and VTEC kicks in the engine starts spitting. Its like a ignition cut, it jerks, vtec engagaes but the jerks are all over the place.

Am using a AEM EMS to run the system. Find below the fuel map and ign map.




Also i have put down a graph which shows everything seems inline, but the box is recording timing errors. The graphs shows the area where the spitting / jerking happens.



Ok, things we have done, we change the ignitor in the distributor just in case, changed spark plugs, checked there is spark all around on idle and off load. I checked the plugs twice they are burning well. I still seem to be of the opinion that the spark plugs are not up to the mark. They are iradium i was using on a all motor H22 before i build this engine, though am not sure of the model number but they are NGK and up to spec. Using Magnacore kw70 wires.

But can faulty spark plugs cause the ems to record timing errors?

What do you suggest could be my issue? Please help

Kind Regards

 

ANY HELPERS???????

Here is what the T1 and T2 graphs look like after a internal log.

They are recorded over 4000rpm and -3.5 psig over 50% throttle.



Uploaded with ImageShack.us

Any suggestions?

 

Another graph guys... help

This one is T2 and the cam graphed together.



Regards

 

Does AEM provide any help or base maps for your engine or very similar engine setup.

 

What is your air fuel ratio after 4700rpm? Does your wideband lean out as soon it hit vtec? I will try to dump more fuel where vtec engage. Had the same problem 10years ago, just need hella fuel for vtec. That is assuming you have no check engine light and everything is hook up properly. But it can be many other thing also.

 

Yes they provide base maps with there product.

My map here is based on there h22 all motor map

I compared most of the values they are similar to what a provide.

 

I tried that. It does lean for a moment its just that I have not been able to sort the fuel map cause of this problem.

But I did try dumping fuel it dint help.

 

Is it sputtering and bucking?

 

Squinting and bucking can u explain?
The car is smooth through the rpms then around 4700-5000-5500 it jerks its like a ign cut.

It continues to climb in rpm but the jerking increases andkeeps going.

 

Okay, jerking and bucking (like when a horse tries to throw off a rider).

Too lean will cause the engine to buck. (Note: I am not saying this is the only reason, could be electrical, etc. But this is the main sympton of the A/F being too lean).

Select all the cells for the RPM in which jerking occurs and add fuel. Have someone drive and you add fuel on the fly to see if you can get it to stop bucking.

 

Ok I will try that will update you guys asap. Looking at the graphs do you think the dizzy is faulty?

 

When the A/F is too lean, the A/F will not "light," and thus the engine "misfires." This will cause timing "errors."

 

Yeah my guess is that you need more fuel in Vtec. Maybe take it to a qualified tuner and get it on the dyno. What heat range are the plugs you are using? If you had a high compression H22 you will need colder plugs for the low compression G23. Plus it sounded like you reused the plug from your H22. I would put new OEM NGK plugs for a H22 in it.

 

Am using heat range 7 if I am not wrong.

I thought about the plug issue as earlier on a cooler engine it jerked less than when really hot.

I will add fuel and do the plugs also will change to stock plug wires instead of the magnacore I have now just as a test.

Will update you all tomorrow thanks for the advice guys

 

Magnecore are good wires, thank God you are not using Nology crap. OEM Sumitomo wires are solid performers, too.

 

have you messed with the wiring on this car at all?

 

Yes as the car was obd1 and the engine is obd2b the wiring have been mated.

But at many instances i have checked and recheck the wiring everything seems to be good.

no lose connections etc.

Todays update:

I changed back to OEM wires, got a set of denso IK20 plugs with heat rating of 6, am not able to find those with a rating of 7 ngk or denso.

Anyway, car still misses the same way.

We tried something stupid or crazy you can say. We dumped fuel in and made sure it ran rich 12-11.8 AFR added ign timing.

At almost 43-45 degrees of WOT timing it wont miss fire but the ecu still registers timing errors...

 

Am seriously starting to consider the possibility that the distributor is faulty.

Afterall, its a 15 year old part from honda.

I got it with my old h22 engine with blew early this year.

Am I losing my grip over this?

Your advice is welcome

 

Be careful bout running that much WOT timing.

So, you got the engine to point where it doesn't miss/sputter. A buddy of mine says AEM has trouble with signal pickup and processing. That may cause "phantom," false positives in your timing errors.

 

Trust me it was just a test car is is running 26 -29 degrees.

I agree I also know about the problem of aem picking up signal. Though I have had had his ecu for a year it used to work perfect.

The issue is even if those errors are false but its not possible to run that much timing safely so there is a issue.

 

Is the sputtering gone now?

 

Exactly the same as before.

When on super 45 degree it does not jerk or does it very lightly so u cant feel it.

But on normal numbers.

Still misses the same. Same rpm same missing.

 

When you check your idle ign timing (base) timing with a timing light, what is it?

 

She is idling 10 flat. Synced it to the box with the ign wizard twice.

10 is when I lock it at 10 on the ecu.

 

The engine is seeing/doing 10, but your ignition map doesn't have 10 anywhere.

What part of the ignition map is your engine idling on?