ramicio

iTrader: (-1)

I wanted the TCC to stay locked up even if I let off the throttle. I am sick and tired of hearing my revs flare when the TCC engages. I had a chip flashed to change the temperature when it engages and I mentioned the behavior I wanted. It's not what happened, and I can't get any real information about it.

Can I get this to behave the way I want? Sure I could just get some sort of MPH-activated window switch...but then I don't want it staying locked when I jam the throttle. I also don't want it activating in lower gears.

Somehow the ECM locks it in 3rd, despite the signal from the transmission only opening in 4th. If I do manual 2nd, it engages there, too.

ramicio

iTrader: (-1)

Anyone? I don't want PM advice on who to go to to get a chip burned. I want to know if this is how the ECM is supposed to function. Mine is a 165 ECM. Evidently the 7730 doesn't behave this way... I don't really want to go that route, as I can never figure out how it would work, as I was told that there was no such thing as a 350 TPI in those years...

RBob

iTrader: (1)

You should be able to do what you are requesting. AFAIK the parameters are in the calibration to do this. However, it also depends upon how the trans is wired. If it has ever been apart the wiring may also have been changed.

RBob.

ramicio

iTrader: (-1)

The signal from the ECM is letting go when I let off the throttle. The top gear signal from the trans activates only in 4th gear, and stays on even when not on the gas, so the ECM doesn't seem to be using that information at all. The tuner said there are no other related parameters. He said his stock 305 auto with a 7730 ECM does keep on the TCC.

EDIT: To add, I verify the ECM signal's behavior because I wired the TCC output to the shift light in my digital dash.

RBob

iTrader: (1)

Well, an '87 should have $32B firmware, but it can also be changed to '89 MY $6E firmware. They both have the parameters required to do what you are asking. The TCC unlock when off the throttle is the 'coast release.'

There are also two sets of tables for TCC lockup versus MPH. One set for 2nd & 3rd, with the other for 4th (high gear).

RBob.

RyanJB

He wanted to retain $32B for the cold start injector. The TCC is set to not unlock unless under heavy throttle or low speeds.
The ABWT bin with 32B I used doesn't have a "coast release" parameter, would it be under something else? TCC min load limit hysteresis?

RBob

iTrader: (1)

Try these:

RBob.

ramicio

iTrader: (-1)

I apologize. My TPS wasn't set to a high enough voltage. I've been messing with it today, for unrelated reasons, and the TCC staying on without throttle just started working out of the blue. Even if it reads 0.54 volts at the TPS with the engine on, it seems to need to be increased a little bit just to get this to work. It seems to read lower with the engine off, so I set it to 0.54-0.55 volts with the engine off. It does work, so I apologize for not covering all avenues.

ramicio

iTrader: (-1)

Well. I spoke too soon. Now it's a problem on my end. When I drove it and it worked, the idle was way high, so I did the procedure to reset the IAC. I needed to really increase the idle set screw to even get it to start, so obviously I had to readjust the TPS. Now it doesn't work. I tried adjusting the TPS low or high. Nothing... Can anyone help?

ramicio

iTrader: (-1)

Okay, so I went and adjusted the idle screw to the point where the throttle plates just aren't sticking, then I adjusted the TPS to as close to 0.54 volts that I could. It's adjusted all the way it can go and still can't reach up to 0.54 volts. Then I went for a drive, and it worked. As soon as I shut it off and turned it back on, it stopped working. What is wrong with this POS of a car?

ramicio

iTrader: (-1)

Any ideas? I don't want to just throw parts at this thing.

ramicio

iTrader: (-1)

I had a spare IAC and TPS. I disassembled and cleaned the IAC. I cleaned out the passage and throttle plates. I went to re-set the idle, and the screw needed to open the blades quite a lot. Then after adjustment, I adjusted the TPS back down. Then I went for a drive, and of course, it was idling at like 2k if I was moving. When starting, the idle would surge to like 2.5k before coming back down. The TCC didn't stay on during this run. So I adjustedthe screw back down, put on a different TPS, adjusted that, and went for a drive. Still no proper TCC action. There is nothing in the manual for troubleshooting this. The coolant temp. sensor is fine. The O2 voltage cycles. The person was supposed to have removed the AIR functions on the PROM. The EGR doesn't even try to open. I know when it tries, because it's blocked up and throws code 32. It threw code 32 yesterday when the TCC was acting as it was supposed to, so whatever the deal is is also messing with the EGR. Can someone please help me and advise me on what else to check?

ramicio

iTrader: (-1)

Found the vacuum line to the EGR solenoid fell off. Made no difference. If I adjust the idle properly, it doesn't behave correctly (starts with a crazy high RPM and idles high while coasting). Tested a bunch of sensors AT the ECM, to rule out bad wiring. Any that are capable of being tested with a multimeter are good. Can anyone please help me?

ramicio

iTrader: (-1)

I just got a new MAF and now it's giving me code 36. I went through the entire flow chart and it got me down to a bad ECM. My ECM isn't even grounding out my burnoff relay. I replaced the quad driver from a junk yard 7730 ECM. Still no go. The only thing else I have connected to that driver is the TCC, and that works. I was thinking of normal logic, that a low to the driver should trigger it, so I probed pin 2 of U9, and it was low. Looking at a datasheet for a similar driver, I see now that it needs to be high to trigger the driver. There is perfect continuity between U9 and U3, and between U3 and connection D12. I am going to throw in my stock chip tomorrow, and see if it pin 2 ever goes high. If it doesn't, I will be getting another ECM.

Oh, and the MAF I bought used from a member still doesn't start my car. But I guess I'm just a jerk-off that knows nothing and needs to spend hundreds of dollars on a scan tool and laptop to tell me that a MAF that won't let my car start is bad, even though I can read a schematic, understand digital logic, swap [micro-]soldered components between PCBs, and read a factory service manual that doesn't ever tell me I need a scan tool, but instead says that if the car runs better (or at all) without the MAF plugged in, then the MAF is bad. I guess I, and the engineers at GM, know nothing, especially when they tell me to adjust my TPS to 0.54 volts, but some self-proclaimed "expert" on the phone tells me I should be adjusting it "by ear."

Oh, and I still never did get a refund for this chip that doesn't make my TCC behave the way I want it to.

RyanJB

You received a refund on 12/13/15.

If the TPS is less than 1v at idle its "within spec" from what I have been told

ramicio

iTrader: (-1)

You're right. I apologize. It just wasn't showing as a refund, but just money sent, so when skimming through I didn't see it.

If the book calls for a specific voltage with a tolerance, that's what it should be. The newer ones are non-adjustable and just given a large range of where to set it, because those ECMs automatically zero when powered on.