Did the HSR swap this weekend, and got some wierd scanning result on my way home from the shop... (did'nt reprogram the prom yet)

With Superram, O2 in LH header, WB in RH header

60mph 0,94vTPS 2000rpm 50kPA 2.43bpw 128BLM 14.5WBO2

With HSR same PROM only intake swapped

60mph 0,94vTPS 2000rpm 50kPA 2.9bpw 150BLM 13.3WBO2

But the milage was exactly the same

I will start diagnos the problem this weekend..any ideas?

My guess is a leak at LH side causing lean condition on O2 sensor, but I dont hear any leak.....

 

Strange, but yeah, the problem is on the side with the NB. Could be a vacuum leak to one or more of the cylinders on that side, which would lean them out or misfire them. Could be a spark plug wire problem. Could be some other misfire problem. Could be exhaust leak (yeah, they're not always easy to find).

 

Changed header gasket- Same results
Changed O2 sensor - Same results
More timing- Same results
Less timing- Same results

Today I swapped intake gaskets, will test tomorrow..........otherwise IM OUT OF IDEAS!

Suggestions???

 

New intake gaskets
New plugs
New wires--- Same results!!!!!!!!!

 

Swap injectors side to side and see what happens.

Also, in the morning, spray some water on each header tube on the bad side to see if there are any dead or weak cylinders. See if any evaporate the water slower.

 

Yeah, will swap injectors today, will also see what my WBO2 sensor looks like.

If the injector swap isnt workin, I maybe suspect that RH is burnig some oil- fooling the WBO2 sensor to show "rich"..... Damn..if its burning oil, maybe I cant trust the WBO2..... now I dont know which sensor to trust anymore,,,,,,,

Hopefully I will have time to go to the garage tonight......again...

See here for scan results

https://www.thirdgen.org/techbb2/sho...40#post2388140

/N.

 

Update:

Changed the injectors between LH/RH. Same resuts.........

At 50 km/h @ 1500 rpm WB= 14.7 BLM 142
At 90km/h @ 1850 rpm WB= 13.5 BLM 142
At 110km/h @ 2200 rpm WB= 12.7 BLM 142

Then I unplugged the Aux input to LM1

At 50km/h @ 1500 rpm WB= 14.0 BLM 134
At 80km/h @ 1650 rpm WB= 13.8 BLM 135
At 110km/h @ 2200rpm WB= 13.5 BLM 139 this has always been lower before..

I also checked for AC current and I had 30v between the +/- nomather what rpm on engine, is this normal?

Anyone with more ideas? I'm out......................

 

We were having the same issues on my friends formula with the HSR. I ended up pulling the base manifold and running a straight edge along it. The passenger side of the HSR was warped bad the straight edge would wobble back and forth. This caused irratic air fuel due to cylinder sharing and leaking fuel outside of the ports instead of in the head. We sent it back, holley confirmed the problem and sent us a new one. We just got it monday and I ran a straight edge this time before the install and it was fine. May want to check this before you pull your hair out, I have almost none left now.

 

We welded the manifold to be able to port match it to 1206 and then machined it, so I think it would be straight, I also changed intakegaskets last weekend, and I saw no signs of a leak, this time I put RTV sealant on both sides to make sure.........

/N.

 

My HSR ran rich at lower RPMs (from the SVO injectors) and lean at higher RPMS. I suspect it's just an airflow characteristic of the design. Your runners are *really* small now.

 

this is not at high rpms, this is at 1900-2200 rpm and in closed loop, and if I do A WOT I get down to 10.8AFR @ 5500 rpm *pig rich*.....

 

At 2,200 rpms, are you under any boost? I assume not, being you stated you were only at 50 Kpa.

Swap the WB on the LM-1 to the other side of the motor same goes for narrow band obviously. Re-datalog. If it still shows same funky results, swap back on your old intake just for sanity purposes.

If the problem goes away with old intake installed, then you have a problem with the HSR base - maybe due to welding/porting etc... It may appear perfect with a straight edge, and it probably is, BUT, the angle of the plain that meets up with the heads may be slightly off.

I had a similar problem with the LM-1 showing rich when the BLM's were lean - arround 145 - 150 (actual AFR was 11.8).

My advice.......... go all the time open loop. Manually tune VE table until the LM-1 is happy for part throttle and Wide Open. Then throw the narrow band in the garbage!

It's worked for a Bunch of boosted motors that still use this ancient 730 ECM.

Just my $.02