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Discussion Starter #61 (Edited)
Right now I wouldn't even try to drive it to the gas station to put e85 in it, but yea I was planning on 50/50. I doubt it can even back down the driveway currently. When I tried to run the 83mm maf it acted like this on stock injectors. Hopefully I can get it going enough that I can diagnose some stuff. With more fuel hopefully more air will help.

I am running 550s on stock MAF with SAFCII. It worked fine for pump gas with a bunch of negative correction, and even better once i started running 50/50 E85 so that i could run less correction. Did you plan to start running some E85 eventually? If so, and the amount of correction you are running turns out to be an issue, you can try that sooner rather than later.
 

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Discussion Starter #62
Woohoo. She likes air. Tried again with the stock maf and no good. Hooked up the 2 wires on the arc2 and put in the ford maf and big cone filter and she’s running great. Got idle dialed in fairly well. Just going off of o2 sensors on the lcdbc they are both cycling quickly high and low. Just washed her and waiting for it to cool down.
 

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Regarding installation of the BlackStealth EBC, I finally located the firewall grommet using a diagram. It was actually hidden behind what appears to be a layer of sound insulation material which is why I couldn't see it from inside.

My new problem is that the silicon vacuum hose won't stay on the black box's nipple port. The nipple is smooth and tapered and the silicon hose is slippery so it just slides off with any movement. Putting a clamp on it doesn't solve the problem either, it only slides off faster from the pressure since the tapered nipple doesn't have any ridges for the hose to grab onto. BlackStealth suggested putting hair spray on the nipple & inside the silicon hose, letting it dry, then using a clamp. Will that work or do any of you have any other suggestions, like maybe inserting a short section of rubber vacuum hose between the silicon and the black box? (The nipple should really be ridged like the brass tees that I used to connect the other end of the hose into a vacuum line - no problems at that end.)
 

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Discussion Starter #64 (Edited)
I used 4mm hose and then a zip tie and its not going anywhere. Maybe your vac hose is the larger 6mm? Ive only been up to 9.5lbs of boost on it though, once I go to 15-18 it might come off.

Luckily for me my firewall has 2 holes drilled in it right under the battery tray to the right of the fuel filter and I can shove anything through there lol.
 

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Yes, BlackStealth recommended I use the thick-walled 3mm/6mm (inside & outside diameters) silicon hose.
It fits very snugly on the 3 mm nipples of the brass tees, no clamp needed, but slides right off the 3mm plastic nipple. I guess hair spray glue is the next step. If that doesn't work I'll have to rig up some kind of wire harness to hold it in place.
 

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Discussion Starter #66
Well got the car back up and on the road tonight. While cleaning up everything I accidentally plugged the boost solenoid into the auxiliary port of the lcdbc. Drove around for ever and was only hitting 4.5psi. I got the arm1 hooked up for now and while it isn’t as good as the aem wideband I have sitting here But it’ll work until my friend can weld in the bung. I got the low mid and accel dialed in quickly. my settings are nowhere near others lol. I’m at +2 low -7 mid +4 accel. High I had at like +5 and it ran like crap once boost hit because it was way rich. Moved it to +2 after reading and all is well. So then on to the next problem I was only getting 4.5psi boost which hey not a bad thing to start slow. The lcdbc diagnosed that I hooked the boost solenoid into the wrong port when I did a test and got nothing lol. I had duty cycle at 75% and still only 4.5psi which lead to testing the solenoid.

I’m currently running the Supra pump not hot wired. I’ll see how far it takes me until I’m running lean.
Done for the night but can’t wait to Give it some more!
 

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Discussion Starter #67
So driving the car yesterday I got on it while getting on the highway and hit 15.2 psi, car was running good but then a few miles down the road it started acting funny. doing about 70 and giving it a little gas caused it to hiccup. Got where I was going and was there for a few hours. Restarted it and then got a CEL for intake air sensor using ford 83mm maf so unsure how reliable that code is. Limped it home after it stalled on me and I had to set the mid knob on the arc2 to almost full negative.

Maybe fuel pump is cutting out, maybe boost leak? or maybe just the MAF intake air sensor is messed up. I dunno, I will diagnose more when I can.
 

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If it was a minor to moderate boost leak , you'd really only notice it when you lifted off from being hard into boost. If you are noticing it just cruising and not in boost you probably have a massive boost leak to the point where air is getting in during vacuum, probably blew off a clamp or coupler. Fuel cut under boost is pretty obvious as well as it usually cause the car to buck somewhat. I'm betting since it was your first time back to boosting over 10psi you blew a clamp or hose off. Also if since you haven't hot wired the supra pump yet, I suggest doing the fuel pump relay bypass if you haven't already done so, to make sure it is getting high voltage all the time.
 

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So driving the car yesterday I got on it while getting on the highway and hit 15.2 psi, car was running good but then a few miles down the road it started acting funny. doing about 70 and giving it a little gas caused it to hiccup. Got where I was going and was there for a few hours. Restarted it and then got a CEL for intake air sensor using ford 83mm maf so unsure how reliable that code is. Limped it home after it stalled on me and I had to set the mid knob on the arc2 to almost full negative.

Maybe fuel pump is cutting out, maybe boost leak? or maybe just the MAF intake air sensor is messed up. I dunno, I will diagnose more when I can.
Never ever run the Mid knob on anything but -7. It should be locked in place. Your settings are not that peculiar. Accel may be a click too high but that can be simply from other mechanical issues you got going on related to vacuum leaks, bad throttle body shaft seals, injectors, fuel issues, etc. You always have to run the ARC-2 with one of the Ford MAFs. The 83mm aluminum one can run on stock injectors but not the plastic 90mm. I don't know about the Granatelli polished 87mm but I have one. Also, the ARC-2 translates the MAF signal in a really weird odd way that I have not been able to make sense of so don't get too hung up on knob settings. If it works it works. If it is way off from a lot of the other settings you read on the forums, then you probably have some mechanical issues to sort. You shouldn't ever install bigger injectors and a piggyback until your car is running solid on stock maf and injectors; otherwise, you will be chasing your tail fixing issues. I go through this stuff all the time with owners I'm helping out semi-locally that want to upgrade their cars or just get them running good again after sitting for years driving maybe 400 miles in that period of time. Unless your maf sensor went bad, I doubt it's related to the ARC-2 for the IAT CEL. You may have wired something wrong or may have a wired connection at the ecu that is spotty when you installed the ARC-2.

And just to give you an example of how weird it gets with the ARC-2, I ran 1000cc injectors with it on E-85 and the stock ecu. Settings were -1 Low, -7 Mid, High +8, Accel +3. When I swapped in the flashed ecu, changed my injector size to 700, put in the injector latency values, and so forth the car would not run no matter what settings I tried on the ARC-2. I doubled the maf size, nothing. Returned that to factory settings. Changed the maf adder from 64 to 500 because of what one other flashed ecu ARC-2 user said. That seemed to work but the car was super lean getting into any throttle. Even adding fuel in the maf smoothing did nothing. The maf scaling was just way off. So I changed the injector size back to 1000 with injector latency values from the evo forums, maf adder to 500, and reset the ARC-2. I think I came back out at +3, -7, +8, and +2/+3. Everything worked great, boosted well, and there was enough fuel but my ecu load is scaled way down and no changes in chrome would make it work. This resulted in seeing maybe 120 ecu load and WOT timing numbers of 24-25 degrees lifting the heads in mid 20s boost. I confirmed this with only one other DR-750, ARC-2, E-85, flashed ecu owner and he had to rewrite his ignition timing map to shift it all to the left but it worked for him after that making 680whp at around 30 psi. So moral of the story is go with a GM MAF/MAFT combo if you want a much nicer, easier, and more direct translate of the maf signal. Bob got the algorithms figured out much better. I already have a 3.75" Delphi MAF and MAFT to swap in to retune before I swap in my AEM v2. The only reason for going through the iterations is just to get more familiar with the ins and outs of tuning each one since I'm getting a number of people reaching out to me to tune chrome with various maf options as well as AEM.
 

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Discussion Starter #70
Actually the car was running great on stock maf, stock injectors and the arc-2. So at that point it got the 660 injectors, and ford 83mm maf. I had no choice but to change the mid once the problems started coming during that drive. Car wouldnt accelerate up an on ramp lol. Its been at -7 though. I agree that something mechanical isnt right.

I do need to look through my manual to find what my throttle % should be and timing at idle. Id like to verify that atleast.
 

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Actually the car was running great on stock maf, stock injectors and the arc-2. So at that point it got the 660 injectors, and ford 83mm maf. I had no choice but to change the mid once the problems started coming during that drive. Car wouldnt accelerate up an on ramp lol. Its been at -7 though. I agree that something mechanical isnt right.

I do need to look through my manual to find what my throttle % should be and timing at idle. Id like to verify that atleast.
TPS shouldnt read below 10% in the logs when you have 0 pedal input. In torque datalogs mine sits at 13 i believe, and ive seen others in the 11-13% range.
 
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Actually the car was running great on stock maf, stock injectors and the arc-2. So at that point it got the 660 injectors, and ford 83mm maf. I had no choice but to change the mid once the problems started coming during that drive. Car wouldnt accelerate up an on ramp lol. Its been at -7 though. I agree that something mechanical isnt right.

I do need to look through my manual to find what my throttle % should be and timing at idle. Id like to verify that atleast.
It's tune related and/or mechanical. The low and accel knobs are a balancing act and effect driveability in a huge way if they aren't balancing each other right. Mid always stays the same and high is only for WOT. I haven't seen it effect any other load areas for driving or knobs. Those Denso injectors are a good brand so I'd hate to say that is the culprit but it'll be one of the things to rule out eventually. You could swap stock injectors back in and go through the car with a fine tooth comb to reverify everything is ok mechanically.
 

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Discussion Starter #73 (Edited)
My TPS is at 14.1 no pedal

I kind of think that the fuel pump may be the issue. It came with the car, who knows how old it is, I didnt have it tested. The injectors I had tested and they all tested fine except I didnt get a flow sheet for some reason, guy said they were all fine though. I also didnt hotwire the fuel pump yet.

One thing I do know is that the last few days the car ran good, but once it got some boost into it (15.2psi) Is when the problems arose lol. I think maybe I have a boost leak that comes and goes, or only holds under certain conditions. Maybe the fuel pump or relay gave it up.

The CEL is not constant and is only present at idle (some times) and flickers on and off. Or maybe its the MAF being pickey. Im getting a lot of symptoms of a bad MAF.

  • The engine is very hard to start or turn over. - not really it starts fine as long as the arc 2 settings are happy
  • The engine stalls shortly after starting. - It will idle, though sometimes a bit rough
  • The engine hesitates or drags while under load or idle. - with the arc 2 settings that used to work, YES
  • Hesitation and jerking during acceleration. YES
  • The engine hiccups. YES
  • Excessively rich or lean idling. Maybe, hard to tell since no wideband and I have the arc2 and ARM1 telling me whats going on
Its possible bumps are causing a bad connection somewhere. I will start it tonight with the arc2 settings that used to work work and see what happens.
 

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I kind of think that the fuel pump may be the issue. It came with the car, who knows how old it is, I didnt have it tested. The injectors I had tested and they all tested fine except I didnt get a flow sheet for some reason. I also didnt hotwire the fuel pump.

My TPS is at 14.1% with no pedal

One thing I do know is that the last few days the car ran good, but once it got some boost into it (15.2psi) Is when the problems arose lol. I think maybe I have a boost leak that comes and goes, or only holds under certain rpms. But I also need my wideband put in so I know whats going on there, rich vs too rich is also a problem. Maybe the fuel pump relay gave it up since Im not hotwired.
You need a fuel pump hotwire then and an aftermarket fuel pump(255-400 walbro). You're just out of fuel most likely.
 

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Discussion Starter #75 (Edited)
I have the supra fuel pump which I have read is hit and miss on some cars without a hotwire. I assumed I would see the ARM1 go towards lean if I was losing fuel. It stays rich so im not sure its the supra pump not flowing enough? Maybe the ARM1 cant catch it in time to tell me. Its right when boost starts. But I should say, car was running pretty good for the last 2 days and not doing this hiccup thing, or needing to have the arc 2 messed with in such a drastic way.
 

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I have the supra fuel pump which I have read is hit and miss on some cars without a hotwire. I assumed I would see the ARM1 go towards lean if I was losing fuel. It stays rich so im not sure its the supra pump not flowing enough? Maybe the ARM1 cant catch it in time to tell me. Its right when boost starts. But I should say, car was running pretty good for the last 2 days and not doing this hiccup thing, or needing to have the arc 2 messed with in such a drastic way.
The Supra fuel pump pulls 20 amps at max load according to Larry McCoy. It needs a lot more amperage than the stock fuel pump and thus a heavier gauge wire than the factory stuff. It just demands much more. I’m actually surprised how many people never hotwire their fuel pump when installing an upgraded one. It’s a simple $30 mod if you’re not too lazy to pull plastics to run it under the carpet lol.
The ARM-1 sucks for anything but full rich or lean because anything inbetween won’t show you an accurate result. You are better off looking at the 02Vs on a datalog for a slightly more accurate reading of your fueling. Both the 02s and ARM-1 are using the 0-1V signal. That’s why a 0-5V wideband with 5x the resolution and a more intuitive gasoline AFR scaling is so much better and easier to use.

I bet what you are noticing with your fueling issue is that the demand on the stock wiring can’t keep up with the stock wiring. You are still using the hi/low fuel relay and on tip-in with more throttle, there is more demand for the fuel pump possibly switching to the high side of the relay for increased output would be my best guess, and since the stock thin wiring can’t supply a high amperage quick draw it takes a little bit to catch up. You get a momentary lean issue and then it clears up. That is exactly what I have observed on a local’s VR4 with no hotwire. It was cleared up and solved with a hotwire kit install. You should go ahead and try it since you honestly shouldn’t be running more than 12-13 psi no matter the turbo or fuel pump if you have no fuel pump hotwire.
 

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Discussion Starter #78
Got it. Thanks for the info. I have a Hotwire kit here I just wanted to see what would happen without it. I need to take a 4 gauge power wire out so I would run the new Hotwire when doing that. I have the aem wideband here too. The arm1 was to just get me going and I guess I haven’t noticed anything bad enough to not turn up boost. So I just kind of did it. Also have the Honda aem fpr if I need it.

I’ll set Boost to 10-12 until I get all that hooked up. got ahead of myself!

getting that vac line shut seems to have helped lol.
 

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