(Not sure if this would be the appropriate board but iam desprate)
I am currently in the middle of swapping a TPI engine into a Nova and am stuck in hard spot.

I have swaped the engine, bought a standalone wiring harness and 2 730 computers. I was going to try and start the engine, with it in the car, before i installed the fenders, hood etc. The fuel pump is just pumping gas from a small gas can and is an external mount type. But i have run it to a BIG problem.

I hooked the computer up and checked everything, fuel pump came on, Map sensor hooked up, injectors hooked up, distributer firing, the engine is in time. I only hooked up what i thought the engine would need to just start and run for a couple of seconds this included: MAP, TPS, all injectors, Fuel pump, with a return, Distributer (that has EST a bypass), IAC, Coolent sensor and Air Sensor, it also has a VATS bypass and of course a power and ground wire for the whole thing.

now here is my problem. I was trying to start the engine and the fuel pump case shorted to the chassise. It fried the fuel pump ground wire, but other than that the fuel pump was fine, but everything was not ok. Now when you turn the key to the on position the fuel pump does not come on, when you try to start the engine there is no Spark, the injectors are staying on (checked by watching a test light and spinning it over, the light stays constant on both banks), check engine light does not go off, and I can not get into Diagnostics to pull codes.

What i have checked: There is one main ground wire that everything is hooked to it is fine, i unhooked the ecm and everything and feed power into it and checked it with a test light
i checked the main power wires: one has power all time and a fused link, it is fine, then one runs into a small fuse block and sends constant power to the injectors, and one for the a ecm power source, these are all fine.
All of the main wiring seems to be fine from the looks of it iam going to ohm every wire on it tomorrow.
Basicly now the computer is not sending out any signals what so every, the injectors are not cycling, fuel pump is not comeing on, and there is no spark. I changed the computer thinking i back fed power to the computer when i shorted out the pump but it did not fix the problem.

I would like some sudjection on where to go from here and what you think might be wrong with it. Also VATS does drop voltage because my test light dims when i check it but i have not seen how much. Thank you in advance.

 

'dsw

Retrofits are fun??? Couple of things that I would check.
Check Pin B1 12v fused from battery. It also ties into C16 and 12 volts should be present continuously.
First make sure that you are getting +12Vdc on Pin A6 when ignition is in RUN and START position. Check appropriate fuses.

I am assuming that your engine is turning and starter is working normally.
Injectors should get +12 on supply wire, the other wire is pulled low by ECM to activate injector. So, having 12 volts on both wires is normal when injectors are not being fired by ECM.
Check your fuel pump relay, coil should read about 90 to 110 Ohms and power contact should very low resistance (0.1 Ohms and less). Fuel pump is controlled by ECM via pin A1. It's should be around 12 Volts for about 2 seconds once ignition key transitioned into RUN position.
While fuel pump relay is energized check Pin B2- tan/wht- Fuel pump signal from the relay it should be +12Volts.

//RF

 

I will check these things. I have already checked my fuel pump relay and it is good, the ecm is not sending power to energize the relay, i have checked all my fuses 100 times with ohm meters, test lights, and by looking at it and they are fine.
I was also sudgested to check the ignition modual, i did and it was bad. WOULD THIS CAUSE THESE SYMTOMES: No Spark (of corse), No Fuel pump, no start, injectors staying on constantly.

Tell me if i am wrong but i am thinking the computer uses the igniton module and the distributor like a cam sensor to tell when to fire the injectors. My module was tested at Advance Auto and it was bad in every aspect that the machine tested. And also would the ecm have to see that the module is good in order to turn the fuel pump on, because the injectors are staying on constantly, if the fuel pump did come on it would not build any pressure.

 

'dsw

You do not need ignition module for ECM to turn on fuel pump relay. Dizzy operates on its own accordance (i.e. firing ignition coil) before engine reaches 400 RPM. On the other hand ECM needs to have a reference pulse from ignition module to fire injectors. If it is not receiving dizzy reference pulse it will not pull injector control lines down and fire injectors.

Check all you ground lines - make sure that they are connected to engine ground. On ECM interface verify A11 & A12, D1 are grounded. D2 is a sensor ground and should be grounded near thermostat housing.

Two second fuel pump check takes place before engine cranking - with ignition key going from ACC to RUN position, engine off. It is a part of self check performed by ECM during initial ignition power on self test sequence (POST).


* RAM Error Detection and Corrective Action;
* NV-RAM Diagnostic Checksum;
* High Voltage Disable of ECM Outputs;
* All A/D inputs read;
* All discrete inputs read;
* All pulse accumulator/pulse period/pulse integrator inputs read;
* PWM outputs energized individually;
* Discrete outputs energized individually each 50-100 mSec;
* Check engine light turned off;
* EST mode disabled;
* Synchronous fuel delivery disabled;
* All discrete outputs de-energized;
* All PWM outputs de-energized (0% duty cycle);
* Asynchronous fuel output fixed at 3 msec every 6.25 msec;
* Checksum of nonvolatile RAM calculated;
* One second ECM turn off delay;
* IAC outputs on, but not changing state;
* EPROM Checksum;
* Check engine light turned on.

All of the above takes about 1.0 seconds.

After P.O.S.T check allows functional verification if ECM is running from the PROM. This involves checking for the SES blink at key-on, engine-off. If the SES does the blink it is running from the PROM. The blink is: at key-on, engine-off: light comes on briefly, blinks off, then comes on solid. You get that, you are good to go. No blink off, not running from the PROM. Will need to wait 5 seconds between SES blink tries.

//RF

 

I checked all of the pins from your first post
-Pin B1 and Pin C16: both had constant power of 12v
-Pin A6: When key was in start and run i had 12v
-Pin A1 fuel pump control: when the key was turned to the on position the two second test did not occur there was nothing from the ecm. i check the relay. it was good. i checked the contanst power on the relay, it was good. i unhooked the ecm and fed 12 battery power to it and the fuel pump came on.
-the ingition module was fried anyways so i needed a new on. after replaceing i still do not have spark.
-coil ohmed out to .9ohms i dont know if this is good or bad cause you said anywhere from 90 to 110 ohms.
-Injecters have 12v on both sides when the ecm is not hooked up, when i hook the ecm up ALL injectors open and stay open, when you turn the engine over they do not cycle at all they just stay open the whole time.
-check engine light comes on and stays on. it never goes out unless the key is turned off.
-I cannot get it to go in diagnostics mode at all, nothing, no blink, just constant ses light.
- I have pulled the harness out and ohmed every wire and also fed power through them and checked with a test light just to make sure. All wires are fine. i have checked and double and triple checked grounds,power supplies, and fuses but i have found nothing. i have also change the ecm and still the same thing.
-Pins a11,a12,d1,and d2 all have good solid grounds.
Could possible be a bad ecm, because i have already replaced it once but the replacement came from a JY and i dont know if it was good or bad when i got it. With either ecm the same still happens there is nothing comeing from the ecm no fuel pump, no fuel injectors.

 

Aghhh

We are getting somewhere:

-coil ohmed out to .9ohms i dont know if this is good or bad cause you said anywhere from 90 to 110 ohms.
Above was a reference to fuel pump relay coil. Ignition coil primary side (12 volt side) should be around 0.9 Ohms (which you have) - verify high voltage side just to make sure that you have good coil. It should be in Kohms. I'll double check my coil tonight to verify.

-Pin A1 fuel pump control: when the key was turned to the on position the two second test did not occur there was nothing from the ecm. i check the relay. it was good. i checked the contanst power on the relay, it was good. i unhooked the ecm and fed 12 battery power to it and the fuel pump came on.

When fed +12 volts did you feed right at pin A1 of the ECM interface (ECM was removed) connector? If it the case then ECM never performs FP 2-second test which maybe pointing to VATS problem.

-check engine light comes on and stays on. it never goes out unless the key is turned off.

See my earlier post - it looks like you may have EPROM issue. SES must blink at key-on, engine-off. If the SES does the blink it is running from the PROM. The blink is: at key-on, engine-off: light comes on briefly, blinks off, then comes on solid. You get that, you are good to go. No blink off, not running from the PROM. Get another PROM burned without VATS (use flash chips with G1 adaptor). Or another stand by ECM if handy...

//RF

 

Pin A1: I did unhook the ecm from the connector and fed power into the connector to make sure that i had good wiring.

The harness that iam using is an Aftermarket harness and uses a VATS Generator. I do know that the generator is working because i hooked a test light up to it. the light goes very dim; would this not show that a voltage drop has occured?

I have already change the ECM once, but it was with a JY replacement. COuld i have essentially got a bad ECM from the JY. the ECMs are 730's, but the one from Jy is from a Berreta I changed the PROM from my other ECM (Which is a v8 prom not sure if it is a 5.0 or 5.7). I also tried it with the Berreta prom just make sure that the prom may have been bad, but i am getting the same results out of both of them.

Also I can not get it to go into Diagnostics to pull codes out. I was told that this also could be an indication of a Bad ECM?

 

I do not know much about VATS generators. Perhaps someone else can shed a light on this subject. VATS can be disabled in EPROM or fooled with external generator like you have. It is possible that generator is sending wrong voltage to ECM?! Can change VATS generator settings?

https://www.thirdgen.org/vats_passkey_system
https://www.thirdgen.org/forums/diy-...lications.html

I have a collection of ECMs from JY - couple of them are duds. It is a possibility that your standby unit is a dud. Swapping EPROM between ECM is ok as long as they are the same type - which they are in your case.

I am not sure why ECM will not talk, but there is probably a good reason for it. I just do not know...

//RF

 

If I was you, I'd find a friend with a similar car.
Take your spare ECM, and plug it into your friends car.
Look for the SES sequence. On, Off, On and stay on.
If you get that, your spare is OK. You're done with your friends car, unless he's real gutsy.
If so, try again with your original ECM.
It's highly unlikely you'll damage anything in your friends car, but since it ain't yours.....

 

The biggest problem i have with this is around here everyone has pulled of the TPI in faver of a carb. i know a few people who have corvettes but there all MAF cars so im kinda out of luck.

Anyways thanks for the help i appreciate it a lot, the JY gave me a 60 day warrenty so i will just take it back and trade it for another one maybe it'll fix it.
Really thought the VATS and the ECM are about the only things that i can think of that would cause this to happen.

 

dsw

Stock coil (remote from 89 F-body) reads 11 kOhm on secondary (high voltage windings) and about 0.8 Ohms on primary.
Look for another non VATS ECM or disable yours through EPROM
//RF

 

If i do get another computer that does not have VATS and the EPROM is good. Want i have to get another v8 PRom for it to run properly. Also what if i dont get a no VATS ECM will i still need to delet it in the PROM even though i have the generator, or was you saying that to ensure that the VATS is not the problem.

 

DSW

Take a look here for more information regarding 1227730 ECM

http://www.diy-efi.org/gmecm/ecm_info/1227730/

It is a very good read regarding 7730 ECM and its close cousins. The fact that you are no getting SES light to blink on - off - on with key ON, engine off may indicate that ECM is hosed or you are still missing supply voltages, grounds.

1227730 ECM uses $8d mask, Byte $016, bit 4 enables or disables VATS. TunerPro allows you to alter VATS setting in EPROM and you can burn a new EPROM with right tools - read stickies.

//RF

 

Yes, and no. All you need, is a car with an ECM in the same family.
You're not gonna try and start the car. As RFmaster posted, there is a sequence the ECM goes through at key on. If you can plug yours into a car with a similar ECM, and you DO get the blink sequence, then you know that the ECM is OK, and that's about all you'll want to know from that test. You really don't care at this point, if the chip is the same or not, just that it blinks.

Another thought.
Disconnect anything and everything having to do with the fuel pump. Key on. Do you get any kind of blink sequence at all ? If so, the ECM is alive. Might still be sick, but it's alive.

Still another thought.
Since the fuel pump is isolated by a relay, you may have blown a fusible link someplace, popped a fuse, smoked the harness, something like that, but it's not likely to have blown the ECM.

If I'm understanding you right, coils, VATS, PROM, all that is irrelevant UNTIL you get the key on blink sequence. All VATS does, is to keep the injectors off so the engine will not start. You will get the blink sequence, fuel pump, spark, etc. but no fuel, so without the blink sequence, VATS isn't the problem.

Note: ANY blink sequence indicates the ECM is alive and the processor is running.
If it has no sensors, no VATS generator, you'll get on for one second, off, then a fast blink, indicating the peorcessor is alive, and has found an error, and set a code.
A bad or missing PROM will get a fast blink only, but you'll still know the ECM is alive.

Hope this sends you in a good direction.

 

Since the fuel pump is isolated by a relay, you may have blown a fusible link someplace, popped a fuse, smoked the harness, something like that, but it's not likely to have blown the ECM.

-THe harness i have is an aftermarket harness. There are only 4 power wires: One is hot all time and has a fuesed link, but it is fine; 2 of them run from a fuse block and to the injectors when the key is on; i know that the injector wiring is good because when i turn the key on the injectors come on and stay on regardless of what the engine is doing, they will not cycle at all when you turn the engine over; the fourth one comes from the fuse block and goes to the computer and supplys power when the key is on.
-I am pretty sure that all my wiring is good. I have pulled the harness off and ohmed every wire on it, I also back feed power through the wires and check with a test light to just double check.
-My grounds all run into one main ground. I have checked them the same way. i also grounded the wire to the engine and used a volt meter to make sure that it is grounding good and it is.
-My ECMs are not giving a blink what so ever nothing, just a constant light. I also can not get it to go into diagnostics to pull any codes out. I will pull the PROM out and see what happens, if the light does blink what could that indicate? A bad PROM, ECM, ...??

 

Now get this. I pulled the PRom out and hooked everything up. the fuel pump came on?????? Turned the engine over i had spark, but now i dont have any fuel injectors what so ever nothing. i put the prom back in and it did the same thing i had spark and fuel pump but no injectors. I changed in my back up Ecm and the same results (spark and fuel pump no injectors). ALso now my Check engine light does not come on and stay on. I am getting power to the injectors and i have a good wire tothe computer but the ecm is not grounding the injectors.

I have pulled my vats generator out and Im going to check the resistance on it just to make sure that there isn't a problem with it.

When everything else was going wrong the Injectors were staying open regardless now they wont do nothig, but i now have spark and the fuel pump is running.

 

This is probably a bad thing.
If memory serves, the ECM provides a ground to the injector to turn it on.
If they are, in fact, opening and staying open ( how do you know ? ) this suggests
a completely fried ECM. Not likely you'd have two that were both failed in the same way, but possible.

Sniff closely. Does it smell burnt ?

If the light does blink, it indicates the processor is running.
If the processor is not running, you won't be able to get it into anything but limp mode, if that still works. No diagnostic mode, no codes set or retrievable.

I'm still bothered by this whole fuel pump episode.
The pump *case* shorted to chasis, and burnt the *ground* wire ?
Something about that just seems wrong.
----------
WOO HOO !! Bravo !
Your ECM is alive, and well ! ( especially if you're getting that on, off, stay on sequence )
Now what you're describing is VATS. Everything works, but the injectors stay off.

 

I'm still bothered by this whole fuel pump episode.
The pump *case* shorted to chasis, and burnt the *ground* wire ?
Something about that just seems wrong.
----------
My fuel pump was not installed into the car. i had it setting there in the engine bay, that has no fenders or hood or anything right now, and was trying to start the engine bofore i put the hood and fenders on. The onlything i can figure is the pump vibratiton caused it to fall off of its unsecure mount on the tire and hit the chassise. Than was just me rushing not doing something right and now casuing other problems.

When i was said the SES light doesn't stay on i meant it is not comeign on what so ever, iam getting no SES light.

This is probably a bad thing.
If memory serves, the ECM provides a ground to the injector to turn it on.
If they are, in fact, opening and staying open ( how do you know ? ) this suggests
a completely fried ECM. Not likely you'd have two that were both failed in the same way, but possible.

Sniff closely. Does it smell burnt ?

I know the injectors are staying on by means of a test light in place of the injectors. the would com on and stay on, when before( i tested everything before i hooked it up to just make sure it was working) the light would cycle when you turn the enigne over. But now the injectors do nothing, the have power but they are not being grounded by the ecm.

 

I pulled my check engine light off of the wiring harness and reinstalled it. Apparently it was not making a good conection, because now it is working. i pulled the codes out of bot the Berreta computer and the F-body computer that i have.
Code 34: this showed up in both of the computers, but i do not have the Map sensor hooked up at the oment.
Code 43: This showed up in only the berreta computer. and is for a TPS sensor or Knock sensor, but neither is hooked up.
Code 46: This showed up in the F-body Computer and is for VATS. the description says a fault in VATS. This must be were my problem is. i have checked my VATS generator and it is in a spec. but it may not be in spec for this computer. the resistance was 1100 ohms which is in a spec.
But if the Berreta doesn't have a Vats then what could be shutting my injectors down? would the berreta prom have anything to do with the injectos not fireing?

 

Little things can sure screw you up !

Says it's working !

Don't know anything about VATS generators. Can't help with that.

Does it have VATS ? What you're describing sounds like a VATS shut down. No injector firings. That's a PROM option bit, so it could. No reference pulses to tell the ECM that the engine is turning will also cause no injector firings.

At this point, I'd run down the PROM code ( should be 4 letters after the ECM part number ) and see if there was VATS in that code, or post the code here so one of us can check it.

Not sure it was ever stated. Do you have a means to edit the PROM and disable VATS if it's enabled ?

 

Ok this thing is just got me puzzeled.
-i wired up my Berreta computer w/ the berreat prom in it. Everything started working fine. I have injecters, spark, fuel pump. I even unhooked the VATS generator and it still works??!
-Ok. so i swap in my F-body prom in and it doesn't work. i have no injecotrs.
This thing has got me very puzzeled. for 2 days nothing has been working with either ecm. and now all the sudden everything is working fine except for the VATS in the F-boy prom. i dont know what is going on, but i hope theis doesn't become an intermidet problem cause it would really suck.

No i dont have any means of editing and Burning PRoms if i could it would be no problem. i was really hopping this generator would work because it would make me feel a little safer when i park it down town for a while. i could just pull the generator out and noone would be able to at leat drive off with my car.
----------
I appriciate the help from both of you. I do not know a whole lot about these systems. Thats why i decided to swap from a card to fuel injection, to learn more about how it works and what it acts like. I am currently enrolled in Tech. for Auto Technition. i figured if this was all that i was going to be working on for the rest of my life i just aswell star learning about it now; i figured this would be a good way to learn, and it has.

 

Cflick,
i noticed that you have a 87 surburban with a buick 455. i got a 82 c10 that i want to do the same thing with. i got a few question.
-what motor mounts did you use
-did you use any kind of headers, or did you keep manifolds

 

A bit off topic, so PM sent.

 

could you send it again i did not recieve it.

I hooked everything back up and everything is work as it should. i tried to start it but i am not getting fuel pressure. pump is pumping and everything. The system has been setting for a while so im sure that the injecters and fuel rail are clogged. I am going to pull them off and clean them and hopefully I'll get some where. I want to say again i appriciate all of the help you two gave me.

 

dsw

Since your application does not have VATS in ignition lock I would strongly recommend that you invest (as a minimum) in the following ECM tools:
G1 adaptor
256k FLASH chip
Moates flash chip programmer
ALDL cable to PC
Cheap Lappy
TunerPRO RT (almost free -$30 donation to program author via PayPal)
WinALDL (free)

ECM's are known to expire - we are dealing with electronics that was built in the late 80's and 90's. I do not like to be at mercy of a $30 JY ECM. Hence if one goes t^ts up I just pull another one from collection, put my latest EPROM, replace NETRES chip with V8 version and of I go. My application is TBI and I can use a number of different C3 ECMs.

Altering EPROM contents is no longer an equivalent of a rocket science nor does it require a degree computer science with emphasis on real time systems. TP does a very nice job and there is a lot of support for 1227730 on line. There is a learning curve - no doubt about it, but end results are well worth it - see my video of my conversion.

Your engine combo maybe a bit further from a stock than you think. Tuning with TP will result (eventually) in much better running combo than any of your Carb friends can ever have. Yes, it will take time, perseverance and a lot patience digging through some of these pesky problems.


//RF

 

I am planning to invest in some programming tools.
-I already have a laptop that some one just gave me, the battery is not that great but i can deal with that.
-I have been doing a lot of research on the subject but am a little confused. This is because i dont actually have anything to actually program. I have already downloaded both TunerPRo and WinALDL, and also Moates. i have piddeled around with the tunerpro, but i was just mainly looking around seeing what all was in there. I tried to download some .bins but i could not figure it out.
-I have also been looking in to making my own cable, but i have read some discourging things about the homemade ones not working for some people. But for around $10 you can build a $30 dollar cable sounds interesting.
-Iam pretty sure that this engine is nothing but stock seeing how it came out of a Truck. The engine was rebuilt but it was back to stock. I bought the Wiring and the Intake seperate.

 

dsw

Develop a plan - and set priorities.

From my experience -
First - I got ALDL cable and WinALDL with lappy talking to my 7747. This was like opening a gate to another dimension. I can see what my engine is doing. I was able to collect some drive data - which was used later to compensate my VE tables with tuner pro. Lappy battery can be replaced or you can get DC-DC converter for your lappy.

Second - Getting TunerPro RT requires additional files (bin, xdf, and ads for 730) all of which are available from Moates website. Learn how to alter bin file with TP - read TunerPro FAQ and docs.

Third - Get G1 adaptor, a known good (spare) ECM, Flash Chip (27C256 or eq.) and flash chip programmer. Stock EPROM will be replaced with G1 adaptor and FLASH chip.

Forth - Programming FLASH - using new Bin - doing some drive testing, accumulating more data - modifying bin more.

//RF

 

Don't know if it'll work for your machine, but I'd strongly recommend a hard look at
dynamicefi.com
You won't need chips, burners, adapters, any of that. Just a laptop with a serial port
( or USB adapter to serial ) and a copy of an editor. ( I like Tuner Pro )
Note that I do think it's rather severely underpriced, but that didn't stop me from buying one.
IF it'll work for you, it's the biggest bang for the buck that I've found.

 

i have one as well

 

Well i got a little up date if you dont mind it being a little off topic.

I tried to start it today and got a lot of wanting to start but not starting, some backfires, and spits and sputers. I believe it is flooding because I checked my injectors and some of them are leaking, but this is all good though, it means iam getting fuel pressure and that the computer is fireing the injecters. but i could not try anything else for the simple fact that my battery died. As for getting injectors i thought about ging to the junkyard but i wulll parbley just another set of bad ones.

 

dsw

Looks like the base timing is way off. To simplify initial start up, I would disconnect EST wire so that timing is not controlled by ECM. This will automatically set code 42 which you can clear by disconnecting battery power from ECM.
Also, check Cyl #1 is approaching TDC on a firing stroke and rotor is lined up with #1 Cyl post (take cap off after marking cyl post on the dizzy body). You can manually advance base timing from 0 to 10degrees by twisting dizzy. We're getting close.

//RF

 

Alright i will try this tomorrow. i have to go to work now, but i will definatly give it a shot. I am pretty sure that the timing is dead on(by looking at the rotor and bringing cyl 1 onto the compression stroke), i have checked it probley 10 times, but i will again to just make sure.

 

I checked the timing again this morining and i was a little off. I twisted the distributor and got everything right.
I got it to some what start. It fires up and runs for a second and then dies, it also will not do this unless i have the throttle open, but this is probably because i have the wrong throttle body. i have the early throttle body on a late manifold, i just figured that out today. ( big slap on the wrist)
I also checked to see if my TP sensor was working right and i dont believe it is. when i checked the voltage at WOT it was lke .062V and with it closed it was somewhere around 4V. Isn't this backwards? shoudln't it be lowvoltage at close and high at open. but i also know that i have some leaking injectors, could this also make it only want to start with the throttle open.

Oher than these could of things i believe that i am making good progress. 6 months ago i was crying cause i had wrecked it.

 

Swap pins C&A on TPS. At idle you should have 0.5 to 0.6 Vdc at Pin B. WOT should be around 4.0 Vdc. ECM is confused!!

//RF