What's wrong?

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Apr 1, 2008 | 05:34 PM
  #1  
I bought a 1986 truck with a TPI intake on it. It ran ok for a while, since I have had it I replaced the intake(holley ram), harness, computer, chip, distributer, injectors, sensors(affordable fuel injection),cam, lifters,timming chain and balancer. I got it running, ran ok then the code said the 02 was running rich. I don't know what happend, a mechanic said it was the ecm, I had it tested but that's NOT the problem. i want to get diagnostic software and cable all in one shot. Can someone tell me where to shop or what happend to my truck. 1990 730 ecm
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Apr 2, 2008 | 04:41 PM
  #2  
Re: What's wrong?
I'm not an expert, but this is how I understand the MAP based TPI stuff to work. If you changed the cam and now the manifold vacuum at idle is lower, that could be one cause for your problem. The ECM would be confused, it would think that the engine was under more load than it realy was because of the lower vacuum readings from the MAP sensor. It would then add extra fuel to compensate. In open loop this means the engine runs rich all the time, no major deal, but not ideal either. Out on the highway when it trys to go into closed loop, it might not be able to adjust the base values enough to lean the fuel to the point of getting a good O2 signal. It would then turn on the light. The way to fix this is to get the ECM to tell you what it thinks and then tweak it till the block learn values stay centered.
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Apr 2, 2008 | 06:12 PM
  #3  
Re: What's wrong?
The cam I bought is shown in the TPI fuel injection swappers guide hydraulic 212/218 @ .050 .444/.444 114 degrees lobe seperation for stock TPI with aftermaket chip. When I ordered the system from AFI they asked everything including what cam i had. The mechanic I have looking at it said he will look at the 5v referance signal and let me know. I am interested with dynamic efi seem to be everything you would want to test and program, any input?
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Apr 3, 2008 | 12:39 PM
  #4  
Re: What's wrong?
Quote: I am interested with dynamic efi seem to be everything you would want to test and program, any input?
I've been looking around and trying to put all this stuff together in my head. I liked what I saw about the Dynamic EFI, except for making soldering type mods to my ECM. I'd prefer not to make permanent changes to anything, especially the ECM itself or the harness. I like the way their system has flash banks so that you can have 8 different ECM setups that are switchable live.

I've always had an interest in the Megasquirt. What I'd like is to be able to plug a Megasquirt straight into my harness. I don't mind adding some additional wiring, but I'm not willing to cut anything.

I want to be able to collect real time information from all the sensors and also I would like to be able to make changes to the tables while the engine is running. I'm kinda handy with electronics and computer type stuff, and I know how to solder, so I'd likely go the kit route if I could.
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Apr 3, 2008 | 04:46 PM
  #5  
Re: What's wrong?
I have an extra 730 ecm so I would have dynamic install the board for me. I don't want to cut into my harness ether, that may lead to problems. I don,t have much knowledge on megsquirt, but I have seen it posted. I just need GOOD software to troubleshoot but being able to change tables would be nice. I have to find out what has gone wrong. I just read that megasquirt can run without the stock ecm. You have to put the ends on the harness you get with it for the sensors yourself, I have my old harness so that part would be possible.
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Apr 3, 2008 | 07:11 PM
  #6  
Re: What's wrong?
I have just been convinced that megasquirt IS the was to go!
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Apr 3, 2008 | 07:51 PM
  #7  
Re: What's wrong?
Quote: I have just been convinced that megasquirt IS the was to go!
It has been a few years since I've followed the Megasquirt development closely. Back then it was pretty cool stuff, but I'm really impressed now. I'm trying to keep an open mind until I see/understand the rest of the offerings. I'm not just interested in what I can do with the camaro, but I also have a motorcycle I'd like to convert to EFI.
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Apr 3, 2008 | 08:00 PM
  #8  
Re: What's wrong?
I was just told on another post to get my truck running right before megasquirt or I will just add to my problems. I have the numbers off of my engine, I would like to know where to look up them up at to know if I have a 350 or 305.
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Apr 3, 2008 | 08:15 PM
  #9  
Re: What's wrong?
check out mortec, they should have your casting numbers listed in there.

If you cannot find info on that code on the net, try going to the dealer and talking with one of the techs. Usually they can pull up the code on the computer and it will usually give a step by step diag to find out what the problem is.
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Apr 3, 2008 | 08:29 PM
  #10  
Re: What's wrong?
Thanks, I will do some searching and post what I find.
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Apr 3, 2008 | 08:40 PM
  #11  
Re: What's wrong?
Yes, it is an 87-95 350 block with one piece rear main seal, now I need to know why it's running rich.
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Apr 3, 2008 | 08:47 PM
  #12  
Re: What's wrong?
I keep posting in the MS post instead of this one

Another trick is to get some carb cleaner and spray around suspected vaccum leaks. If there's a leak, the idle will jump a little.
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Apr 3, 2008 | 09:43 PM
  #13  
Re: What's wrong?
I have tryed that a few times, no idle change.
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Apr 3, 2008 | 10:11 PM
  #14  
Re: What's wrong?
man, there's gotta be a vacuum leak somewhere, thats the only thing I can think of. I went from TBI to carb to HSR, so I havent had alot of TPI experience. But 10-12 in at idle with a "stock" cam, something's leaking in air. I wonder if this could be caused by a bad O2 sensor?

What all sensors did you replace? MAP, O2, IAT?
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Apr 4, 2008 | 04:11 PM
  #15  
Re: What's wrong?
I have replaced the o2 three times, they are only 20 bucks but I think they are all good. At one time I was told maybe the o2 senson is not far enough into the collector to read correctly. The shop is doing more checking, is there info on what each sensor is suppost to read. The mechanic has a snapon scanner, would the diagnostic software and laptop tell you better what's wrong?
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Apr 6, 2008 | 11:02 AM
  #16  
Re: What's wrong?
I stoped by the shop to check on my truck, said the tps would not show pecenteges, replaced it, now the iac is NOT working at all, so i am using the old one, i think i am going to run the ecm power to the battery only to see if the fuse block is the problem, the other thing i want to now, could the distributor be interferring with the ecm?
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Apr 6, 2008 | 05:06 PM
  #17  
Re: What's wrong?
I ran the power straight to the battery seem to help and the iac is working. I checked vacuum, it is 15 inches. Seems to run better with the pcv valve disconected. Drove it home, ses light came on with a code 45 rich exhaust. It is the same as when I brought it to the shop. I need help.I have a laptop, i need to to know what software is good and a cable all in one stop shop.
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Apr 7, 2008 | 09:29 PM
  #18  
Re: What's wrong?
http://www.moates.net/index.php?cPath=49
This will get you logging all data from the ECM.
There is also AKM cables, He has cables too.
For logging software,
Download the free version of TunerPro (TunerPro.net), ScannerPro (still beta testing) or even the Datamaster (from TTS motorsports)

You will need the correct definition files to log your setup.
Being that it is a 1990 with 1227730 ECM it should be a speed density (MAP) setup with $8D program.
For each program there are different file extensions so you'll need the file that works for that program.
TunerPro = ***.ADS files for dataloging
ScannerPro = ***.ADX files
Datamaster is downloaded as the $8D version so no other files are needed.
DM only lets you log for 20 times before you need to buy it, the others are free to use but are Shareware and the author would like to eat too , so if you like it, shoot him the low donation and register.
HTH

Edit: Forgot to mention that using a single wire o2 with headers may allow the o2 to cool off at idle and cause the ECM to go into open loop control.
Using a 3 or 4 wire heated o2 solves that problem.
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Apr 8, 2008 | 04:52 PM
  #19  
Re: What's wrong?
If I get tunerpro, defenition files and a cable to see what the ecm is doing, then if I wanted to change something would'nt I have to reburn my chip? Would I be able to do all and more with megasquirt?
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Apr 8, 2008 | 10:11 PM
  #20  
Re: What's wrong?
IMO, before throwing the whole system out and starting over with MS or other you will need to find out what the problem is currently. It could just be a mechanical adjustment problem or sensor giving you fits that will transfer over to the new setup. You could get a chip adapter from Moates for not much money and find an inexpensive burner to make your changes to the setup you have now.
Not that there is anything wrong with the EBL or MS, just that it will not correct an existing problem unless its completly tune related. I don't believe that is the case if the system had run good at one time. The hardware changes you've made have certainly created the need for readjustment of fuel and spark. Only some logging can clear up the mystery by seeing what is going on during operation. The 730 with $8D is supported well and has allot of documentation explaining how to tune it. Check out the sticky in the DIY_PROM board here for more info.
I just feel you may be setting yourself up to have a big letdown if you change the entire system out and are stuck with the same problems.
You should be able to make the existing setup work ok, then move on to another system if needed to enhance the features or ease of tuning that you can't get with the current ECM. I'm a bit biased because I run that ECM and code in my car and am quite familiar with how it operates.

Just wondering, what is the code on the chip you are running?
AUJP, ANHT, or something should be on the sticker on the outside of the ECM or on the memcal chip under the cover.
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Apr 9, 2008 | 05:38 PM
  #21  
Re: What's wrong?
I believe I have found out what happend. When I got the code 45. I found that the small filters in the injectors ended up in the regulator! I called affordable fuel injection, they said to run them without the filters so I did. Now I replaced the injectors with the old ones MUCH BETTER! I can't drive it far because the old (TPI) injectors are too tall, rail won't bolt up. So I would guess the filters dumped krud in them causing my problem. I will have to wait to get my injectors back(ford injectors??), meanwhile I can order the cable and get the software to start. As far as the 02, is a wideband needed for tunerpro? Will the heated 02 help with idle? I don't see the letters you stated on the chip just 57TPE650 on the sticker that covers the eye. The chip came from affordable fuel injection. I see the K and N where did you put the tps?
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Apr 11, 2008 | 05:19 PM
  #22  
Re: What's wrong?
Where do I get a heated sensor and can I get a wideband that is heated?
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Apr 11, 2008 | 09:30 PM
  #23  
Re: What's wrong?
For an NB sensor "AFS-74" is a 3 wire heated o2
Power to heater, Ground, and signal out
"AFS-75" is a 4 wire o2 sensor
Power to heater, heater ground, signal out, signal ground.

Wide Band o2s are heated by the controller. Thats how they work.
Jp
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Apr 13, 2008 | 04:05 PM
  #24  
Re: What's wrong?
Thanks for your knowledge, I will order one.
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Apr 14, 2008 | 05:17 PM
  #25  
Re: What's wrong?
I have recieved the moats cable, I have 19lb injectors in it till I get my 24's, should I wait to tune it with the 24's or run with the 19's?
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Apr 14, 2008 | 05:53 PM
  #26  
Re: What's wrong?
What's wrong with tinkering now and tinkering later? I don't see how any harm could come from it. Have you done any data logging yet?
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Apr 15, 2008 | 04:50 PM
  #27  
Re: What's wrong?
Not yet i'll check it out today. After I posted last, I was thinking the same thing, log now and log later so I can see the differences of both size injectors.
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Apr 18, 2008 | 06:10 PM
  #28  
Re: What's wrong?
Change of plans, I am going through the truck harness and wanted to put my own switches and push to start button, now I have to get sum relays so I don't burn nuthung up. I called Affordable fuel injection to check on my injectors and they said they did'nt get them, I sent them two weeks ago, @#it happens!
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Jun 29, 2008 | 12:02 AM
  #29  
Re: What's wrong?
took my truck out for a drive and found that I am getting about ten miles to the gallon, NOT good, I am getting an adapter to plug right into my pocket programer, looks like I have to see what is on the chip to see how it was programed. What should I look at first, second, then change to help me?
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