New Problem...No power to injectors 944S
12-26-2017, 03:24 PM
#46
That doesn't act like the dead AFM/MAF I mentioned. What is the fuel pressure when you are cranking. If you haven't tested with a gauge, I'd say that's the next test. I might also be inclined to have someone spray starter fluid under the air filter as you crank so see if it seems to fire.
12-26-2017, 04:54 PM
#47
Rennlist Member
Hi Tom. Somewhere I mentioned I checked pressure at 3.8 bar which should be what the S gets I believe. It is there when cranking too. I was thinking the same thing. I’m trying to figure the best way to add gas into the intake...tried just before the throttle body. I was checking compression with a different gauge then afterwards it fired for a second. Don’t know if it was the fuel or what. Such a problem child.
12-26-2017, 09:04 PM
#48
Oh, sorry, missed that. Personally I wouldn't try to add liquid gas, but rather pop the air filter out and spray starter fluid in where the air is being sucked in. If the motor started a bit after pulling plugs to check compression, you have to wonder if it is flooding and needed to air out a bit? Try holding the gas pedal to the floor to let in max air while cranking, and see if that helps it catch.
Time to approach this form a flooding stand point then. What can be the causes? I've tried two sets of injectors and the result is the same so if it is getting too much gas then the injectors are staying open too long. The FPR is fairly new. Would the fuel damper have any effect? I tested and it does hold a vacuum.
12-26-2017, 09:42 PM
#50
12-26-2017, 09:48 PM
#52
12-30-2017, 01:44 AM
#53
Rennlist Member
Been following your thread and issue. Listening to the video you posted it sounded just like my 944s track car that was almost impossible to start. It was always flooded at starting but once running ran great. We put a fuel pump cutoff switch in and started cranking without fuel pump. It would start and immediately I'd turn on pump. So you ask where am I going iwth this. Well we found out the problem was that we'd eliminated the hose from the plastic "J" part of the intake manifold. In making a track build simple, we figured that the hose just put oil in the intake as it pulls in the oil mist from the AOS. By chance one day I took the plug off and it started perfectly. Turns out the "S" needs that tube/bleed open as the DME is expecting that air leak. It might be worth a try to unplug that hose on the intake and see if it starts. If so either its clogged or has some type of restriction. Part I'm talking about is hose marked 5 in diagram below.
01-06-2018, 02:35 PM
#54
Been following your thread and issue. Listening to the video you posted it sounded just like my 944s track car that was almost impossible to start. It was always flooded at starting but once running ran great. We put a fuel pump cutoff switch in and started cranking without fuel pump. It would start and immediately I'd turn on pump. So you ask where am I going iwth this. Well we found out the problem was that we'd eliminated the hose from the plastic "J" part of the intake manifold. In making a track build simple, we figured that the hose just put oil in the intake as it pulls in the oil mist from the AOS. By chance one day I took the plug off and it started perfectly. Turns out the "S" needs that tube/bleed open as the DME is expecting that air leak. It might be worth a try to unplug that hose on the intake and see if it starts. If so either its clogged or has some type of restriction. Part I'm talking about is hose marked 5 in diagram below.
01-06-2018, 04:31 PM
#55
I'm going to suggest that you do not have proper compression. Do a compression check and report back.
(I believe that you have the camshafts mistimed. The pictures in the factory workshop manual on page 15-111 have some unusual orientations and, if you look at them incorrectly, the valve timing is all wrong.)
(I believe that you have the camshafts mistimed. The pictures in the factory workshop manual on page 15-111 have some unusual orientations and, if you look at them incorrectly, the valve timing is all wrong.)
01-06-2018, 04:36 PM
#56
I'm going to suggest that you do not have proper compression. Do a compression check and report back.
(I believe that you have the camshafts mistimed. The pictures in the factory workshop manual on page 15-111 have some unusual orientations and, if you look at them incorrectly, the valve timing is all wrong.)
(I believe that you have the camshafts mistimed. The pictures in the factory workshop manual on page 15-111 have some unusual orientations and, if you look at them incorrectly, the valve timing is all wrong.)
01-06-2018, 04:58 PM
#57
While I understand that you are satisfied with the cam timing, etc. the real proof of good valve timing is good compression. I know that it's a pain, but, considering the problems that you are having, eliminating lack of compression should be considered.
01-06-2018, 05:26 PM
#58
Sorry I should have said I did check compression but I really need a better tester than the Harbor Freight one that never seats well.
EDIT: Actually I have a leak down tester to also try.
EDIT: Actually I have a leak down tester to also try.
01-06-2018, 05:38 PM
#59
A leak down tester would be adequate, but not as telling as a compression tester with a threaded connection at the spark plug hole.
01-06-2018, 06:21 PM
#60
