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something else to add to the list:
-check engine grounding and battery output pathways. I think a ground strap is not present on the passenger mount. I've read quite a few stories about how poor engine ground can effect things. I notice it seems the alternator struggles when I turn the headlights on at night. You can hear the fuel pump whine change. I'm not sure why that would be. But its all a bit suspicious.
ugh okay I went to do "monitor TPS voltage and see if it has glitches around 0% (could eliminate this by seeing if problem appears at other throttle positions)"
I connected OTC 2000
Monitored "REL TPS" (relative TPS position)
Flooring the pedal, I get 79%...hrmmm
Popped hood and moved throttle manually while watching OTC 2000 through windshield, to 79%...definitely not full throttle. I'd say a significant amount of rotation left before its WOT.
Looked at accelerator pedal linkage in cab.
UHH... did I do that? Maybe I did. But if I did, it was years ago. I'll have to check FSM and see if there is supposed to be some kind of spacer or whatsit there instead of the nut.
And Im not sure why that would prevent full throttle actually. It would appear a spacer on the other side, where the pedal arm grabs the cable, would be missing, and thats what would cause the linkage to not pull all the way. Or maybe the pedal is bent. Or who knows. I'll have to get under there and try to figure out whats going on.
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http://i242.photobucket.com/albums/f...psrylvuqis.jpg
okay I fixed that. I replaced the nut with a much thicker rubber spacer, and confirmed that at full pedal travel the actual throttle plate is maxed out, and the OTC2000 reads 100%.
I remember doing that nut now. Years and years ago. Weird..the cable must have stretched further because I probably did the same verification I'm doing now.
- - - Updated - - -
hmmm...this should be fun to read :)
"noticed that all of a sudden my AFR's were 15+ at WOT and I could only generate 7 psi boost." ...sounds familiar hrm
http://www.turbododge.com/forums/f4/...e-maximum.html
I add a spacer there to bring the gas pedal up so heal and toe'ing is easier. If anything it would make the throttle open farther.
okay with engine off, OTC 2000 says map voltage is 1.5V.
at 21 inhg on the boost gauge, the map voltage was 0.42V
so checking and backing the timing off a few degrees is out of the question? pretty easy and free to do? the power may be lacking in the other areas but it will at least give you an idea if the computer isnt pulling enough timing at that certain rpm range?
also, when i "tested" my coil, the ohms were still in spec, but the kv voltage wasnt there, so unless you have a scope to test it with, it would be pretty hard to tell if there is a fault.
good catch on the tps/throttle cable though, but if its stretched that much, i might be looking for another from the junkyard. ive had 2 fray on me and actually stick the throttle wide open before, not a fun situation...
id be trying to figure out how to get the knock sensor hooked up and helping you with the tune, it will save you more than hinder you...
I think I may be on to something here:Quote:
Originally Posted by OmniLuvr
So after it stumbling HORRIBLY as I described, I changed a couple things at once (shame on me, I know):
-flipped spark plug wires around in cap so fresh metal was facing the rotor
-swapped rotor for one that was in like new condition
-plugged map sensor directly into intake plenum on its own line (well..through the baro solenoid still, but otherwise directly to plenum. It was on a vac block with several other things)
-disconnected PCV valve from plenum and left it hanging (consequence of doing the map sensor direct..I stole the PCV's dedicated port on the plenum. The crankcase still has its ventilation system functional under boost, just not under vacuum, by doing that.
And then I went for another drive. I did 5 or 6 full power runs and there was no stumbling during them! Thats a HUGE change from before. There was still very minor stumbling at very light throttle and load. But I was able to do the full 1st, 2nd, 3rd runs and I have not been able to do that before with the MBC controlling boost.
So to really kill the crap out of this problem, I'm going to put the map sensor back to how it was, and see if the problem comes back, and do it back to back to make absolutely sure that its map sensor hose length/isolation thats the issue with this. And if so, then I shall use all my powers to mount the freaking map sensor DIRECTLY on the plenum, stabbing this issue in the heart and causing it to pierce the night with its screams until it is dead....DEAD forever I tell you
I also logged data during these runs, and captured a few of the very minor "stumbles". But since I dont know when exactly the time stamps occurred in the log, i can't seem to find them. So I shall have to do it again and note the time when it happens.
most of your issue was probably the tps signal. If the cal is only seeing 79% and NOT WOT, then obviously fueling is different. In addition I'm a firm believing in having a dedicated map signal. It may not matter in your case, but it is best to have a undiluted signal, so I would leave it where you have it now, directly to the manifold.
and YES, hook up your knock sensor asap. I hardly doubt seeing knock and pulling timing would have caused the issues you had, but there is no need to disconnect the sensor for testing if your scan tool does not show a severe pulling of timing by the ecu.
He has no place to mount the knock sensor right now though. Not using a factory manifold.
Still need to have the baro in the map circuit unfortunately or we could get away with what every manufacturer is doing these days with a speed density system and mounting the map directly to the intake. But like electromotive has stated for years, Dedicated map line and as short as possible is the way to go. This Vac block craze that mostly is going on over on TD is stupid. Why are we using technology from 80's and 90's Fords when we know Mopar was way ahead of the game when it came to electronics back then.
Cindy, I found my thread from 2008 where I describe exactly the same issue. Can you check it out and tell me what you think?Quote:
Originally Posted by glhs727
http://www.turbododge.com/forums/f4/...stage-5-a.html
Welp the time may have come for me to figure out some way to mount it. I suppose popes idea of chamfering the side of the #2 or #3 flange and drilling and tapping a hole would be the easiest to do in-car, otherwise I'd have to pull the intake. But not sure how it would respond since it would be off center.Quote:
Originally Posted by GLHNSLHT2
Okay, assuming that the MAP sensor is the main cause of my issue, then I'm going to really try to cut down on the map/baro hose lengths and distance to plenum. Luckily the plenum end plate is right next to both of them, so it may be a perfect excuse to make a custom map/baro mounting bracket that does the whole job, with the bonus of mounting the 3 bar map tidily.
I only datalogged two runs from above.
In both of those, 2nd gear reached around 18psi, but 3rd only 7 to 10psi.
I'm thinking maybe the wastegate actuator isnt pre-loaded enough?
http://i242.photobucket.com/albums/f...ps73dafd62.png
http://i242.photobucket.com/albums/f...psbade5447.png
spark plug wire measurements:
1- 3.2k, 12"
2-2.6k, 11"
3-2.7k, 11"
4-3.4k, 14"
coil- 5.3k, 23"
is it bad I'm using different length wires? thats how it came from autocrap.
the wires say 7mm, made in usa, double silicon ultimate heat protection
The spring clip on the coil side of the coil wire fell out when I took it off. Not sure if I did that taking it off or if it was already broken.
bought spark tester..doesnt look like one on website anymore..functionally the same tho i think
http://i242.photobucket.com/albums/f...ps9hhbxf6q.jpg
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Plug wires are fine for stock, carbon core type wires.
What are your AF readings now? Do you have a vacuum pump and a fuel pressure gauge?
You probably won't get more than 20-25K volts using that tester.
for the coil I got 30k consistent spark, 40k intermittentQuote:
Originally Posted by turbovanmanČ
for the wires I got 25k consistent
that style of spark tester is the best type to use because its one of the adjustable types. open up that spark gap to 1 inch and you can tell real quick and easy if you have a weak coil or not- blue spark good, yellow spark bad. hook up a scope if you feel like doing so. under testing with a 1 in gap we were getting 40kv+ at the plug with a similar canister style coil setup.Quote:
Originally Posted by turbovanmanČ
you don't really need to do that though, blue spark good yellow spark bad is all you really need to know.