Running Smooth...but not quite there

[smokin_dodge]

Ive got a motor out of a wrecked '94 svx in an 86 vanagon. the engine is running smooth, idling where it needs to be idling, but doesnt seem to quite have any power until you get it into a couple thousand rpm

i have noticed that when i drive around town it has power but seems sluggish when its getting going, real comfortable around 35-45 but hard to accelerate without flooring it. on the highway it feels like it doesnt want to push past 50-55 and then you pass 4000 or so(tach is messed up) rpm and it runs like a champ - even throws you back in your seat.

i was getting a code 24 and 56, IAC and EGR, took both off and cleaned as per chilton manual. put everything back together with all new vacuum hoses and check valves. no more codes - but still doesnt seem to have any power

ive also done the "quick ecu dump" in case it was in limp mode - no change
pulled all 6 injector plugs 1 at a time and each one had siginificant impact on idling rpm - so all coils working and no dead cylinders.

The only thing i can think of next is TPS and maybe its not set right. ive tried to read the dc resistance across the circut but have had no real luck.

at this point i am stumped

[SoCal LS-L]

Originally Posted by smokin_dodge

Ive got a motor out of a wrecked '94 svx in an 86 vanagon. the engine is running smooth, idling where it needs to be idling, but doesnt seem to quite have any power until you get it into a couple thousand rpm

i have noticed that when i drive around town it has power but seems sluggish when its getting going, real comfortable around 35-45 but hard to accelerate without flooring it. on the highway it feels like it doesnt want to push past 50-55 and then you pass 4000 or so(tach is messed up) rpm and it runs like a champ - even throws you back in your seat.

i was getting a code 24 and 56, IAC and EGR, took both off and cleaned as per chilton manual. put everything back together with all new vacuum hoses and check valves. no more codes - but still doesnt seem to have any power

ive also done the "quick ecu dump" in case it was in limp mode - no change
pulled all 6 injector plugs 1 at a time and each one had siginificant impact on idling rpm - so all coils working and no dead cylinders.

The only thing i can think of next is TPS and maybe its not set right. ive tried to read the dc resistance across the circut but have had no real luck.

at this point i am stumped

When you test the TPS you look for voltage change across the arc while its plugged in with the key on.

This also could be a symptom of a stuck open IRIS valve.... have you checked it to see that it closes completely?

The H6 is more of a high revving engine anyways, by design it produces most of its torque in the high end. Mine also feels sluggish until about 4000 when the IRIS valve opens, then it takes off.

[longassname]

The SVX only comes with an automatic transmission and has a 2500 rpm stall speed. The stock timing maps in the ECU don't have any timing below those RPMs so you won't get any power at low RPMs with the manual box you have in your vanagon. You may have the only vanagon out there without ECUtune software but there is good news....now you can get the recently released Stage1Av1 which will really get you going.

Originally Posted by smokin_dodge

Ive got a motor out of a wrecked '94 svx in an 86 vanagon. the engine is running smooth, idling where it needs to be idling, but doesnt seem to quite have any power until you get it into a couple thousand rpm

i have noticed that when i drive around town it has power but seems sluggish when its getting going, real comfortable around 35-45 but hard to accelerate without flooring it. on the highway it feels like it doesnt want to push past 50-55 and then you pass 4000 or so(tach is messed up) rpm and it runs like a champ - even throws you back in your seat.

i was getting a code 24 and 56, IAC and EGR, took both off and cleaned as per chilton manual. put everything back together with all new vacuum hoses and check valves. no more codes - but still doesnt seem to have any power

ive also done the "quick ecu dump" in case it was in limp mode - no change
pulled all 6 injector plugs 1 at a time and each one had siginificant impact on idling rpm - so all coils working and no dead cylinders.

The only thing i can think of next is TPS and maybe its not set right. ive tried to read the dc resistance across the circut but have had no real luck.

at this point i am stumped

[smokin_dodge]

hmmm, i always thought it had something to do with the iris system. if smallcars numbers are correct there is a double in hp at around 4100-4250rpm - completely what my engine is doing..

[longassname]

The plot you are talking about is an old dyno plot of my car on the dyno at mastro subaru when I first developed stage 1. The plot with a huge drop in power at low rpms is a plot of when we were lucky enough to catch the well known and much lamented intermittent hesitation stock SVXs experience while we were on the dyno. While that hesitation is common with the stock ECU tuning, you shouldn't be experiencing it all the time. It's an intermittent nuisance that happens when a few different conditions coincide. All versions of the stage 1 software elimate that hesitation and improve acceleration for the SVX. The last couple versions of stage 1 also addressed and greatly improved performance at the lower RPMs an SVX with an automatic never sees.

Originally Posted by smokin_dodge

hmmm, i always thought it had something to do with the iris system. if smallcars numbers are correct there is a double in hp at around 4100-4250rpm - completely what my engine is doing..

[oab_au]

Originally Posted by smokin_dodge

Ive got a motor out of a wrecked '94 svx in an 86 vanagon. the engine is running smooth, idling where it needs to be idling, but doesnt seem to quite have any power until you get it into a couple thousand rpm
i have noticed that when i drive around town it has power but seems sluggish when its getting going, real comfortable around 35-45 but hard to accelerate without flooring it. on the highway it feels like it doesnt want to push past 50-55 and then you pass 4000 or so(tach is messed up) rpm and it runs like a champ - even throws you back in your seat.
i was getting a code 24 and 56, IAC and EGR, took both off and cleaned as per chilton manual. put everything back together with all new vacuum hoses and check valves. no more codes - but still doesnt seem to have any power

ive also done the "quick ecu dump" in case it was in limp mode - no change
pulled all 6 injector plugs 1 at a time and each one had siginificant impact on idling rpm - so all coils working and no dead cylinders.

The only thing i can think of next is TPS and maybe its not set right. ive tried to read the dc resistance across the circut but have had no real luck.

at this point i am stumped

That is the way the engine will run, if the IRIS butterfly is not closing.

The valve should be open at Idle, close at 2200, to open again at 4000. If it does not close, you will not have the Inertia system providing the very good torque that it has from 2200 to 4000.

You can see the arm on the valve from the front of the engine, under the manifold. Watch the arm while you raise the rpm slowly from idle to 4500, you should see it change position, at these speeds.

Harvey.