What year did our cars have computers that could be tuned with laptops?
The reason I ask is I have heavily modded my 89 and the car hauls ass but there is a popping noise in the exhaust as I let off, it seems to search for a mixture at cruising speed,and it runs bad at an idle.
I need to find a tuner that works on our cars that can put it on a dyno to tell me what is happening!

Thanks

I am by no means an expert in this. Our (89) still has a computer with a chip. In general, guys get their tune and burn chips to make changes. You can use a laptop with a data cable to monitor the sensors, etc, as you are driving. If you want to make on the fly changes, you will need a moates ostrich tuner. This plugs into the stock computer with a piggyback type cable that is always connected. Check out the moates.net set.

Matthew

One common cause of that is a mal-functioning injector.

On mine, I had 2 injectors going "south" on the driver's bank. Because that's the side with the O2 sensor it would have seen a lean condition and increase the pulse width.

Take a super rich motor and let of the gas....(Especially if any of the injectors are getting slow), the gas hitting the cats is causing the pops.

I'd bet money it's an injector issue.

History on build.

AFR 180 comp heads, zz409 tpis cam, MiniRam, Tpis headers, 1.6 roller rockers, level 5 tpis chip, new bosch 24 lb injectors.
I had it at a shop and they said everything checks out and the car is going into closed loop when it is supposed to. They believe it is in the fuel flow controlled by the computer. I have been in touch with Jim at TPIS and he said to have a tech call him if their any questions on the chip.
My problem is finding some one who dynos, and works on and tunes these type of computers.

first you need to record ata as the car is running, Datamaster tts or tuner pro are good choices. This will give you the info needed to determine were the fueling is at and for any tuner to make appropriate changes. "Popping" from the exhaust on de-cell usually indicates unburnt fuel, I would add some advance in the "closed throttle" table in the tune/prom.

All 89's new the chip burned.

Same for early LT1's

Later LT1's like mine got the computer you can tune with a laptop.

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huh ??
all 87,88,89,90,91 can be done in car w/a laptop, later LT'S can be flashed outside of the car. I believe moates now has some hardware add-ons to be done w/a laptop in car.

Mine was done in the car through the OBD port (OBDII style, running OBDI)

If you know a way of doing the earlier ones, that's news to me.

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I know a way...this is what I use for tunning obdI 91 an earlier. It ties into the aldl and my laptop for real time tunning.
[IMG]http://i44.tinypic.com/308wpyx.jpg[/IMG]

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http://www.moates.net/product_info.php?products_id=169
What mseven is using
Adapter replaces memcal allowing you to connect this device ( emulator ) and tune as you drive from laptop.When you are happy with tune( probally never ) you burn that tune on to a memcal and install in car.
Some of us have it installed in car permanantly because the tune is stored on the unit; the laptop is only the means of adjusting tune.
Going to the track? ; plug in laptop , load your race tune and disconnect,install street economy tune when you get home.
Using correct supporting software , works for most GM pre flash ECM and other brands.

I talked with Jim at TPIS today and ran it down to him what the car is doing. He said that he does not believe the computer is the problem. He suggested resetting the TPS to .62 from the stock .54 and setting the fuel pressure at 45 psi with the vacuum disconnected and then connect the vacuum. He said that stock 6 degrees btdc was a good starting place. He said to try that and call him if it does not take care of the problem.
I think I am going to pick up a new TPS just becuz.

Thanks for the replies. Will keep you posted.

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Computer tuning is not the problem ; it is getting someone who knows MiniRams and their quirks
Many reported tuning problems with MR ; especially off idle lean out and popping .Some have even reported problems with TPiS out of the box tunes.
http://www.digitalcorvettes.com/forums/showthread.php?t=114241

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LOL, ain't that the truth
I became so sick of "ribbon" cables and usb's glitching (including interference issues) because of the ecm/apu-1 location I made a new cable. The apu-1 is now inside the car (90 and the connection speed is still good using a socket booster.
[IMG]http://i39.tinypic.com/10n7yol.jpg[/IMG]
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yes and yes, the tpis tune is typically quite rich, I have one here (stage 5 ) that I have checked out.
To the OP, I believe you will need to get involved w/ logging the car. There is nothing wrong w/making sure there are no mechanical issues, but more than likely the tune needs work. Everything regarding a tune, BLM, SK etc.etc. can only really be known in that method, anything else is only a guess. You can verify the TPS with a vohm meter and just make sure it can "sweep" up and down from .56 to 4.5 (typical voltage) smoothly.

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Notes from 3rd Gen relating to MR tune

"My stage 6 TPIS chip for my MR setup had the same intake popping and way too rich idle, After I got into logging and buring my own I discovered TPIS uses a very tame Spark table with the max PE spark at 30 degrees. They zero out the PE spk add table on my 6E bin.
In addition they do NOTHING about AE where I now have mine close to maxed out in many areas plus they don't touch the stock MAF tables anywhere expecially in the idle and light cruize areas making for a rich idle.
Their way of crutching for fuel is to lower the TPS engagement point for PE from 70% stock at all rpms to 60% at 400 rpms quickly down to 25% at 3600 rpms. Lots of fuel at WOT but light cruizing and idle stink to the point you could take off from a stop sign add too much peddle and the motor will stall out in the middle of the intersection."

Other notes relating to MR problems with cams.
"Not enough acceleration enrichment. This is typical of your combo. The miniram wants a LOT of AE, You also want about 20 degrees of total advance at idle, and you want to ramp out from there to 24, 28, 32. I'd disable PE spark and put it all in the main table."

"The combo of the cam and miniram wants less fuel at idle (a lot less), but more fuel during accel."

"Roughly I had to turn my AE up almost 35% because of the mini-ram"

"The miniram + cam combo wants LESS FUEL than stock in the idle and lower VE ranges, it then wants a quick burst of fuel when you snap the throttle (AE). The cam also wants 20* idle, and wants to ramp out VERY quickly to about 32 degrees."

"How much AE are you adding to your prom. I had to add tons to get mine right. Remember that the Mini-ram loves fuel."

I have heard that from others and read the same over there.
The ones I have here are 2 SD and 1 maf. It appears that they did some different things. These were all comped by a lower inj. constant (ex. 24# in car, 22.4 in the table). .
The only tables that were not stock were the timing and VE tables. VE in the SD's were changed but not in the maf tune. All started at 27.7 at 800 idle, 36 by 1400 etc. and were ramped decently. The max total was 30* above 4200 at wot/load. PE, AE, IAC etc.etc. were ALL stock tables.