What exactly does pin 14 do and go?

[David9er]

A few days ago I wired my aftermarket tach to the wire that goes to pin 21 and it is working fine; however, I found that pin 14 had come free from the plastic connector to the ECU so it was most likely not making contact, I tried to tug on the wire so I could shove it back into the connector but the wire came free from a location that I'm unsure of [previos owner had connected wiring by simply twisting wire together and covering with tape with out using a butt connector or soder]. I can't find a solid green wire in the harness and it seems that due to the length of what is left it was spliced into the wire going to pin 19.
My questions are as follows:
1. does it make sense to splice those together?
2. what should be done with wire 14?
3. the car has had cold start and idle issues since I bought it a few weeks back, would this fix any of those issues?

 

[GST with PSI]

Are you talking about the BISS adjustment mentioned here:VFAQ BISS adjustment?

No, I'm talking about physically adjusting the idle switch. Look at this picture. Remove the black plug, and you will see the idle switch. Loosen the single nut the holds the switch, and turn the switch (should be clockwise) so that the switch contacts the tab on the throttle, and activates (clicks) when the throttle is completely closed.

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I don't crank it continuously, about 10 secs on, 20 off. And yes in that weather the starter does start to slow down so it will kill this battery sooner than later if it keeps up. I wonder if it may have a poor tune on it, the car has an alternate start switch that is wired in parallel with the key so either one will engage the starter and start the car so lone as the key is in the on position I believe this was done to reduce stress on the actual key which has a slight twist to it.

Poor tune indeed. It sounds like the previous owner left your with an utter shit heap of hack jobs and problems. If I were you, I would try and return the car back as close to stock as possible, and then get all the kinks worked out. It's twice as hard trying to fix normal issues when they are compounded by issues other previous owners have caused. Once you have the car running decent, re-apply your mods and have a good running car. Since you don't even know the full extent of how the car was modded, I don't really see that you have another choice. You really need a good understanding of what has been done to the car, to even begin troubleshooting issues. At this point, I feel like you are wasting your time trying to solve problems. Not knocking you at all, but you really need to figure out exactly what you have before you go any further.

 

[David9er]

You hit the nail square on the head GST with PSI. All I'm doing is ironing out one wrinkle at a time, which is fine with me because the wife won't let me put any real money into it till I sell the pickup. I doubt I can get what I want for it till tax time anyway so I have time to fix all this stuff thankfully.

Anyways give me a few days to look at that switch cause the car is literally buried under a foot of snow and I just had hernia surgery Friday. But I am really very grateful for all the help you have given me so far. I even recommended some rep pts for you.

While I have your attention how much tension should the timing belt lose overnight? It is really worrying me because cause its almost enough to skip a tooth but once I have oil pressure it picks up the slack. My guess is the hydraulic tensioner has an internal check valve to keep tension while the engine is off and its just bleeding off due to age and wear. It has plenty of power and outside of the idle runs normally so I seriously doubt it has skipped but to complicate matters it has aftermarket adjustable cam gears so I have no idea how to make sure they line up

 

[92AWDHX40]

Have you got timing issues, over night, if im correct when I did my timing belt once I removed the grenade pin that was, it I never knew, it losing any tension once its done. If that were the case it would seem you there would be problems with the tensioner.

Has it slipped yet, if any doubt I would replace that tensioner.

 

[David9er]

Kinda what I'm thinking, I don't think its lost timing or slipped but you can grab the belt and move it back and forth very easily, I can tell its too loose but once it fires the oil pressure takes over and tightens it.

 

[92AWDHX40]

Maybe time for a Tb job.

 

[GST with PSI]

While I have your attention how much tension should the timing belt lose overnight? It is really worrying me because cause its almost enough to skip a tooth but once I have oil pressure it picks up the slack. My guess is the hydraulic tensioner has an internal check valve to keep tension while the engine is off and its just bleeding off due to age and wear. It has plenty of power and outside of the idle runs normally so I seriously doubt it has skipped but to complicate matters it has aftermarket adjustable cam gears so I have no idea how to make sure they line up

Kinda what I'm thinking, I don't think its lost timing or slipped but you can grab the belt and move it back and forth very easily, I can tell its too loose but once it fires the oil pressure takes over and tightens it.

Assuming your timing belt has been changed in the last 60k, it was changed correctly, and new components were used, I'd say your timing belt is probably fine. If you start the car and let it run for a second, then shut it down and the belt is tight, then you should be OK.

That being said, if you don't know the last time the belt was changed, I'd put replacing it high on my priority list. I'd say ask the previous owner, but judging by what you've said about him up to now, I don't think I would take his word for it. Based on what you've said thus far, I would recommend replacing the timing belt solely because you can't be sure when it was last serviced, not because I think there is currently and issue with the one you have on the car now.

When you shut off the car, the belt will slack up a little depending on where the engine stops at. The valve spring pressure on the camshafts can sometimes force the cams toward each other, making it seem like there is slack in the timing belt. For example, if you have ever done a timing belt install, you'll notice that sometimes the exhaust cam wants to rotate back (clockwise) on its own when the timing mark is placed correctly.

I can tell you "oil pressure" has nothing to do with how tight your timing belt is. Your tensioner isn't bleeding off at night either. If that were the case, your tensioner would most definitely need to be replaced, as it would not be able to do its job. But not the job you may be thinking...

Remember, in hydraulics, fluid can not be compressed. So although there is fluid inside your tensioner, the fluid itself is not actually what is keeping the tension on your timing belt. A spring within the tensioner is what actually holds tension on the belt. Fluid is used in conjunction with valving inside the tensioner to provide dampening for the spring (just like a shock absorber). So, just like shock absorbers do not really alter your vehicles ride height, the fluid in the tensioner has little to no effect on the actual tension held on the belt. The tension is all in the spring. The valving and fluid helps the tensioner move outward quickly, while dampening (and greatly slowing) the movement inward. Like I said above, if your belt is nice and tight after running the car, you should be fine. Good read>>>Hydraulic Tensioners.

As far as the hernia surgery goes, I have a some experience in this area as well. Take it easy, and make sure you do as the doctor says for a speedy recovery. Oh, and try no to cough

P.S. iugrad92turbo, I don't want to be a dick, but I find your posts in this thread (and multiple others) to be a bit far off base. You seem to generalize a lot, and some of your suggestions seem to jump to big conclusions that don't follow any sort of troubleshooting steps/trees. Could you please limit what you post to specifics, and give advice on the same level as the issue? I'm not trying to say you don't know what's up, but I feel like you are a bit misleading.

 

[David9er]

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Yeah I'm gonna wait a few days.....

 

[GST with PSI]

Nice. Evo 8 wheels look amazing on any DSM IMO. So, what is on the car as far as engine management goes? Can't be a stock ECU with the mods you have listed...

And what did you pay for it if you don't mind me asking?

 

[David9er]

I have no idea what is going on with the ECU, I think its stock with some kind of re-flash tune, it may not have 850s, I know it has an after market rail and pressure regulator but I haven't bothered to pull the rail and see what injectors are really in it, I know due to the wiring that an aftermarket pump is in it, a walbro of some kind most likely. The engine and tranny have the aftermarket hard polyurethane bushings and aftermarket mounts so its been out of the car so it's not unlikely that some work has been done inside. I'm pretty confident that the balance shafts have been removed, Its hard to get a good angle but I think the inner shaft belt is gone and there is quite a bit of vibration from the engine.

 

[David9er]

So as far as the idle it is still a little erattic. I'm getting DSMLink V3 soon so I can eliminate the idle switch and find out if its the idle motor or not.

The cold start is the bigger issue at the moument. I thought that I was flooding the cylinders so I have been letting it sit longer between starting attempts. This, however, made the issue worse. What I have noticed is that there is a corralation with the oil pressure. The closer the stock gauge needle is to the bottom operating mark the more likly it is to start. I would say it takes about 1-2 minutes of countinuously cranking the motor to get the pressure close to that range. At this rate I am gonna end up burning out the starter motor, and if I'm lucky I'll drain the battery on a cold day when I can't get it jumped.
Anyways I figure that the lifters, tentioner, etc need more pressure so the engine can crank. My guess is the oil pump is getting weak so it takes its time building the pressure, at idle the oil pressure sits just below the safe mark as well.

 

[92AWDHX40]

Do you know anything about the condition of the oil pump. Even I have link and I have idle problems could be a bad isc, or a boost leak, if you haven't tested it yet, I havnet the entire thread word for word so excuse me if youi did a blt already. It takes a while to start try replacing the coolant temp sensor.

 

[GST with PSI]

The stock oil pressure gauge is grossly inaccurate. I wouldn't trust it anymore than I would the stock temp gauge, and that is to say both are pretty much only good to give you a general idea if there is an issue. The oil pressure gauge is even much less trustworthy than the coolant temp gauge though. On my 90 GST, my oil pressure gauge would drop to zero ever time the car idled. It did this for a decade, and I never saw a single issue. I point this out only to say not to really worry about what the stock gauge is saying, because it is so inaccurate. I highly doubt your oil pressure and starting issues are related.

Did you ever verify if your temp sensor was working properly? And, what is on the car as far as engine management goes? Stock ECU? EPROM chip?

It is going to be impossible to diagnose the car until you figure out what has been modified, and more importantly, what has been modified improperly. I've never heard of a cold start issue as severe as the one your are describing. That would lead me to believe there are some extra factors contributing to your issue that you aren't aware of.

I would:
-Pull the ECU and see if it is chipped, socketed etc.

-Check the CTS and see if it is working properly.

-Swap in a set of stock 450s to eliminate your mystery injectors as being an issue.

 

[David9er]

Did you ever verify if your temp sensor was working properly? And, what is on the car as far as engine management goes? Stock ECU? EPROM chip?
I would:
-Pull the ECU and see if it is chipped, socketed etc.

I pulled it the other day, it is a non-EPROM stock ECU

-Check the CTS and see if it is working properly.

I never did remove it but it unplugging it did make the situation much worse.

As for the cts I unplugged it and the car ran noticeably worse, in fact I think it had a random miss, it absolutely ran much worse without it so I'll inspect the TB tomorrow and report back.

-Swap in a set of stock 450s to eliminate your mystery injectors as being an issue.

I don't have any extra injectors lying around unfortunately, however, after doing some research I am convinced they are stock.
#1 they look like the stock injectors
#2 you said it would need some sort of tune to run bigger ones, and to the best of my knowledge it is not possible to tune or flash a non-EPROM ECU.

I'd almost be willing to bet the P.O. had ECMLink and had bigger injectors and decided to pull the V3 before selling the car and had to shove stock injectors in it to make it work. I'm not sure there is another explanation as to why there is a high volume fuel pump, aftermarket rail, Stainless braided fuel lines, FMIC with piping, etc. The only weak links are the injectors and ECU [which was only held in with one bolt].

 

[92AWDHX40]

Do you have any pics of the injectors look, I you don't have a eprom ecu ecmtuning can solve that issue to fix that. Have a chip put in by them that's what I did, and grab some more fuel. So you haven't checked the cts yet?

 

[David9er]

Again thanks for all the help, I rewired PIN 14 to the TB switch and the idle is down to about 850rpm, so after a BISS adjustment that should be fixed.

As for the cts I unplugged it and the car ran noticeably worse, in fact I think it had a random miss, it absolutely ran much worse without it so I'll inspect the TB tomorrow and report back.

The Items in my profile that have question marks are items that the previous owner claimed it had but I have yet to confirm [he claimed a lot of things to "sell" me the car that I have found to be untrue]

I know that is the A/C switch. I unplugged #5 with the two prongs that look like a "T", and like I said the car started the same but ran like complete shit, there isn't a FIAV blocking plate and the FIAV works normally.

What should I check next?

How many times do I have to repeat myself about the CTS? Unpluging it made the issue worse so it is not bad.

 

[92AWDHX40]

Well ok so what is it doing when you unplug it? do you have any idea of what your next step is since you out, ruled the cts out. ecu is not eprom, do you know what kind of fuel pump, i haven't seen every post on this thread, issues with my computer and the site i suppose, Some posts seem to have gotten off topic about where those two wires go. The problem could be in the wiring, since you bought it with some wiring the previous owner did.

 

[GST with PSI]

Unplugging the sensor doesn't verify it is good or bad, just that the car is seeing something in regards to coolant temp. To actually test it, you need to perform the test I outlined here: http://www.dsmtuners.com/forums/mai...-exactly-does-pin-14-do-go.html#post153364735

You can run larger injectors without a tunable ECU, but the car will run like ass. If the car has an upgraded pump and stock injectors, your fuel pump is probably overrunning the injectors. Post up a picture of an injector and we can easily verify it for you.