Engine load returns back to normal while throttle is constan

4600cc · Post by **4600cc** » Wed Jul 27, 2005 11:29 am

I'm using megajolt with MAP sensor on a vehicle with automatic transmission. While in automatic, I would press throttle say 50% and hold it there, I then see MAP increase and then come to idle loads after it goes through the gears. Is that normal? If I however select a sigle gear, say 2nd, and appply 50% throttle, MAP would remain at 50% and not return like in previous case. Also, at WOT my MAP reads below 100 KPA, it is in 90 KPA range, is this normal?

I am obviously thinking about using a TPS instead of MAP, but not sure if I need to do that? And if I do, I have ECC-IV also using same TPS, can megajolt be made to share the same sensor?

AL

Post by **brentp** » Wed Jul 27, 2005 8:23 pm

Interesting.

I would put a vacuum gauge on the same line the MAP sensor is hooked up to in order to verify what's happening. Where are you connecting it on your manifold?

Brent

4600cc · Post by **4600cc** » Wed Jul 27, 2005 9:44 pm

Ford 4.6L SOHC Modular motor has a bunch of vacuum lines hooked up to upper intake plenum. This plenum looks like a neck rising from a lower plenum, which is a cylinder into which all runners are connected. Fuel pressure regulator, EGR valve, brake booster, etc get vacuum from that upper plenum. I sipliced source for megajolt between fuel pressure regulator and upper plenum.

AL

Todd Charles · Post by **Todd Charles** » Fri Jul 29, 2005 4:47 am

At cruising speeds your MAP readings will be close to your idle readings. Usually around 30-40kpa.

Are you at sea level? What are your MAP readings KOEO? If you are showing close to 100 Kpa then 90Kpa at WOT is showing you have a restrictive intake system.

Todd

4600cc · Post by **4600cc** » Fri Jul 29, 2005 10:23 am

I'm like couple of miles away from Atlantic ocian, no more than couple of feet up. At idle in neutral MAP reads 35 KPA, in gear 42 KPA. Gotta check out MAP without engine running. I could believe that I have a restrictive intake system, all Fords do. I'm replacing mine with a dual stage intake off a Ford truck soon, after I get Megasquirt II up and running.

AL