Engine only runs REAL rich... Why [SOLVED]

OSracer · Post by **OSracer** » Wed Nov 04, 2009 8:13 pm

I can only get my engine to run if it is really rich Im talking in the neighborhood of 450-550 in the fuel table to get it to idle. What would be the reason the only supplied map from Hondata I can get it to run decent on is the LS/Vtec with ITBs and changing from alpha-n to Map. I don't have ITBs of course. What can I post for some assistance? the LS/Vtec ITB map datalogging?

Here is the Engine
B20 Vtec B16A head w/ 84.5mm Bore and matched CC
Crower 402 Cams
Ported and Polished head and Skunk2 Intake Manifold from Endyne
13:1 84.5mm Endyne Rollerwave Pistons
Accel 255cc injectors and Walbro Pump

Here is another scenario I tried
JDM p30 Map
adjusted for injectors and it calculates out only 4% increase from 1.6 to 2.0 ltr with 55 PSi fuel pressure
I took it up 4% on the whole map started the car and it was Lean. Took it up 10% more Still Lean another 20% still lean..... another 10% and it finally went rich Idle was all over like a vacuum leak the only way to get it to settle down is richen it up like the ITB LS/Vtec map.....

Maybe I should just buy ITBs and be done with it anyone got a set for sale?

The only other thing that comes to mind is the EX cam gear is set at -1.5 degrees from when the engine was tuned with an accel gen7 dfi.

Here is a pic of the exhaust and how rich I have to run it. no more than 3000 RPM

fly_n · Post by **fly_n** » Thu Nov 05, 2009 1:41 am

what is your actual base fuel pressure on the rail?

where did u source the reg from? a B16?

OSracer · Post by **OSracer** » Thu Nov 05, 2009 5:12 am

Base Fuel Pressure at Idle on the Rail is 55 PSI the AEM Regulator is adjusted all the way out I can not bring the FP any farther down with the small 255 CC injectors and the Walbro pump

fly_n · Post by **fly_n** » Thu Nov 05, 2009 6:12 am

ok,was thinkin u might have a little 40-odd pound stock b16 reg still attached to the head...

are they low impedance injectors by any chance?
if so,are u using a resistor block?

Post by **Spunkster** » Thu Nov 05, 2009 10:22 am

If you are changing the injector size then also adding fuel to the tables that could be your problem. I highly recommend taking it to a tuner for some assistance if you are unsure of how to properly tune it.

thething96 · Post by **thething96** » Thu Nov 05, 2009 10:26 am

u may want to get a better set of injectors, with more flow(more cc's). your engine might want more fuel, when running properly. I would double check your map sensor. make sure that the o-ring is still in place, if it's not, it will make your car run rich as heck. hapenned to me, so.........

OSracer · Post by **OSracer** » Thu Nov 05, 2009 3:51 pm

fly_n they are 152255 Accel 152255 High - impedance

Spunkster I would love to get it to a tuner thats why Im trying to get it run 1/2 decent as the closest tuners are 60 and 120 miles away here are 2 cals and logs

thething96 Map sensor is mounted to the fire wall and running off the Skunk2 manifold where a EGR would normally connect...

DL1 is a p30 map adjust 25% Cold Idle is great a little lean between 15-16:1 AFR once it warms up Idle is all over you can see it in the data log.

RLYrich is well really rich to get it to idle.

thething96 Map sensor is mounted to the fire wall and running off the Skunk2 manifold where a EGR would normally mount...

If you really want to see something crazy ill upload the LS/Vtec with ITB map and datalog it loves that tune but its so rich as well.

OSracer · Post by **OSracer** » Fri Nov 06, 2009 11:00 am

Here is a cold start with a p30 Map 25% fuel adjusted and thats all.
Idles high with 14.4-14.7 AFR then starts to go lean as the car warms up 3 min in the datalog the idle just stats revving as it gets rich and lean.

OSracer · Post by **OSracer** » Wed Nov 18, 2009 8:03 pm

Problem solved I think...
IACV shows 40 ohms resistance should be at 20 Ohms... ECU can not power the motor as the resistance is too high... Car battery can activate but ECU 12vt can not.

Needs to run rich because the IACV is stuck open flooding the engine with air... No CEL indicated though

OSracer · Post by **OSracer** » Wed Nov 25, 2009 6:52 am

OK after about 2 months of fighting this engine I finally solved the issue!

I purchased this car from its previous owner for $1500 with $6,000 worth of engine and other work done to it. He had an endyn/moroso oil catch can hooked up to it.

I finally got frustrated and ripped the intake manifold off to see he used heater hose to connect the oil return line to the bottom of the block. Well hot oil and rubber hose do not mix there was a hole the size of my little finger where it connects to the block. and the intake manifold was directly connected to the valve cover. so a 3/8ths inch hole / vacuum leak through the block to the bottom of the crank case.

That being said I replaced the hose with "Crankcase" hose not heater hose and it fires up no problems.

The fact I could plug the IACV hole in the throttle body with my finger and it would idle fine basically told me that I have a hole the size of the IACV bypass passage somewhere. I had replaced every singe vacuum line in the engine , well "factory" vacuum lines that is.