I have the above TPI/MAP fuel injection system in my 55 Chevy with a stock ZZ3 crate motor with hooker long tube headers and 700R4 overdrive trans. I have an idle problem and need to find a good tuner that will work on my set up the Charlotte, NC area. I would appreciate any suggestions and thanks in advance for responding to my new tread!
Chuck
Hi, Chuck. Welcome to gearhead-efi.
I don't know how many pay-for tuners spend time here on the forums, but if you decide to make some changes yourself we can definitely help you get started.
I'm not a paid tuner but will be glad to help. But to do that, need you to do the following:Originally Posted by Rednfst1
- Describe the idle issue in detail
- Post up your BIN and a TunerPro .xdl log file or an exported .csv file showing the car idling for 2-3 minutes
- Provide your cam manufacturer, model and specs if you know them (specifically overlap and Intake/exhaust duration at .050", not the advertised values)
Thanks for responding to my post...here's some of the info you requested:
The TPI Multiport system is from Street n Performance located in Arkansas. It's the 90-92 version with speed density. I bought the unit at a swap meet. My engine is a stock ZZ3 GM crate motor. The stock GM hydraulic roller cam specs are .208/.221 at .050 tappet lift. The valve lift is .474/.510. Details of issue and my trouble shooting up to this point are as follows:
* When I start the engine up it runs fine cold then after it reaches 190 degrees and thermostat opens the engine starts speeding up/down (750 to 1200 rpms) 3-4 times then dies.
* Fuel pressure is 45-48 pounds at all times. We have checked the TPS sensor setting and set the volts at 5.5 volts. The IAC is working properly.
The car runs good under acceleration/ steady driving but when you come to a stop with the car in gear it will die pretty quickly unless you keep you foot on the gas pedal keeping it reved up a little over 1000 rpms.
* I have checked for vacuum leaks with carb cleaner and didn't find any. The check engine light goes off once started and it shows no problem codes. The wiring harness came from S&P along with the factory computer that had been modify by same. When I bought the unit at the swap meet I didn't ask what size engine/cam it was set up for which was a mistake on my part. I do not have any tuner software. I'm not sure what you mean by BIN? That's all I can think of now. I can send you a video of when the engine starts speeding up/down if that helps. I also included a couple of pictures of my engine bay with the TPI system. Thanks and hope to hear back from you!!!
Do you know what transmission type the ECM or more specifically the BIN (The calibration burned in to the EEPROM) is set for?
Using an auto calibration in a manual application can cause almost exactly what you describe. However it kinda sounds like you're just not getting enough fuel into the engine once warmed up and idling.
If you're not interested in tuning this yourself and acquiring the equipment you will need to find a tuner locally that will ride along and/or dyno tune.
The man who says something is impossible, is usually interrupted by the man doing it.
Understand. At some time, many here were where you are now. A BIN is the computer file that essentially runs your engine (xxxx.BIN). It's stored on an EPROM chip on the MEMCAL in your ECM. The BIN contains 2 things:
1. the Calibration (all the variable data that can be changed to tune)
2. the GM code that provides all the required intelligence (spark and fueling logic, TCC lock, sensor control, etc.)
BINS have a Mask ID ($8d, $6e, etc.) that defines the code-type for a given ECM (hardware/firmware). The MEMCAL should have a sticker affixed that provides the 4 character Broadcast Code (BCC) (like AUJP, ANHT, etc.). The BCC identifies variations of a mask's Calibration. Without access to at least the BIN's Calibration and a log of what's going on while the engine is running, it's virtually impossible to diagnose anything. With TPI/computer controlled cars, you either learn yourself or trust someone to do a tune for you (IMO not generally recommended because tuning/diagnosing is not a one-time event -- it's a process). It's not that hard and there are many here that can help. But you'll need to do some homework.
My suggestion is that you go to thirdgen.org and read/scan all the tuning related stickies at the top of the DIY PROM forum. There you will learn all the terms you currently don't understand. You can also learn a lot by downloading TunerPro (tunerpro.net), buy an ALDL cable and adapter from moates.net and begin to learn how to create a log. If you feel you will want to learn how to tune, might consider buying an AutoProm (APU1) instead of just the cable/adapter as that is everything you will need. You should also consider purchasing a HDR1 MEMCAL Header as well here (http://www.moates.net/hdr1-memcal-he....html?cPath=64) so you can extract your BIN file. With the extracted BIN and TunerPro, you now have access to the Calibration and Mask ID. But you can't yet change anything in the car. You'll need a way to burn a chip or upload the changes (APU1) after the Calibration is changed, or a way to install the new chip in the ECM. This or some variation is essentially what a paid tuner will have to do.
I realize this is a lot to take in at the beginning. But IMO, tuning is a lot like investing. You can certainly turn everything over to someone else to do it for you, but you darn sure better trust them explicitly and also understand what they are doing. HTH.
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