Ok... I have an 87' 305 TPI pulled from an Iroc that supposedly had around 30,000 miles on it. I pulled the 305 TBI out of my 92' RS, and put the tuned port in its place. I purchased Painless's harness, wired everything up, and tried to start. All it will do is crank. I was just going to replace the fuel pump until I ran into an even bigger problem today. I was cranking the motor over, got out of the car to double check some stuff under the hood(but didnt mess with anything) got back in and tried again. This time it wouldnt even turn over, I got the BRAKE light and then a SECURITY light. This has never happened before, and it really threw me off cuz I thought I was down to one last problem. I thought it would be VATS, but why would it just activate itself now? O yea, and the ECM is from the Iroc as well, but the steering column is not. Could this be my problem? If anyone could tell me whats going on here it would really help me out cuz I'm at a loss...

 

iam not to sure about it not cranking, but i do know that the TBIs have a smaller fuel pump than a tpi. from what ive heard it wont even crank with the TBI pump.


just a question. why didnt you use the 87 tpi motor? TBIs have really small cams.

 

this might seem like a silly idea if you have allready checked it... but pull a spark plug and see if you are getting spark. leave it plugged in and have a friend crank and see if it arcs.

 

More than likely, there is a ground missing somewhere. I played this game for 3 days until I finally got the car to fire up. Are you sure you re-ran the grounds correctly from the other motor? I know there are a bunch on the rear of the heads that connect to the firewall.

As far as the car wanting to not crank at all and your brake and SES light come on, I think this could be VATS as it is happening with my car too. Sometimes it trips for no reason, like I will literally lift my hood, turn the distributor a tad, and the car will not want to even make a noise when I turn the key. 10 minutes later, bam.

Don't pull the fuel pump yet until you verify your grounds. Oh yeah, check your fuses too, and the fuel pump relay.

 

Thanks for all of the quick responses... First off, I did change the fuel pump when I changed the motor, I forgot to mention that, it is a stock replacement for the TPI, no aftermarket stuff yet. The ground may be it, cuz I have only one ground on the rear of the passenger's-side head.

 

My 86 has 3 or 2 grounds on pass. head, and 1 or 2 on the driver head.

Where are you in St. Louis?

 

West County, in Ballwin, how bout you? By the way, just to clarify, It is an 87' 305 TPI motor, I got rid of the TBI motor completely, not just the intakes. I dont know about the grounds with the Painless harness though...its part# 68460... Anyone else used it? O yea, fuses and relays checked, about a million times lol, they're good...

 

you need get the key from the donor car and read the resistace across the chip.Then go to radio shack and get the corect resistors to match chip in donor car key.you have to cut the two small wires going to vats mod and wire the resistors in .gm made 15 diffrent chips for the vats system.maybe this is clear.i have trouble explaining things sometimes

 

I emailed TPI Parts about this, and they said that the 87's didnt come with VATS and that I should just treat it like a normal no-start condition

 

North County, Florissant, try doing a search on Painless wire, I remember reading a good post on them somewhere on the boards, or call painless.

If your CAR is a 92 it has VATS...did you change the computer, or just the chip?

 

I honestly dont know, the guy i bought it from i really dont trust anymore(due to events occuring after purchase) he told me he had the computer from the 87' and everything, that all I needed was to wire it up and it would run. I pulled the wiring harness he hacked up(everything was beyond recognition) and put the painless one in. Ill try and look up the part numbers for it. Is there any way to tell if your ecm is fried? I dont even know if this could be a possibility but...

 

If the computer has not been changed...then the VATS could be the problem,
could you pull it down and post the number on the computer itself, then we can find out.

joe

 

Serv. No. 1226870 HLK
862541 M522080878

I'm not sure which number it is, theres two stickers on it, thats the top one, then heres the other on the side, it has something under the actual number that looks like a bar code or something. Thanks for the help... hopefully one of these are the numbers you need.

16052541 HLK

(then the little bar code type deal is here)
theres also a line of numbers here, but I can only read like half of them

 

Anyone been able to find anything on these numbers? I have looked everywhere for part numbers and for the life of me I cant find a single thing on the PCM's part numbers...

 

I didn't find anything with those #'s, but I will keep looking, and I will let you know.

 

Thanks, I really appreciate the help. Im still looking for some info too, Ill let you guys know if I can find anything.

 

i dont know too much about vats but i can guarantee you it's the column side of the car, theres a "stater" relay it will not engage if it doesnt get the signal to the computer, you would have to bypass that somehow.

 

Ok, just got an email back from TPI parts and they ran the number for me. Its from an 85' TPI and that was the only year they used this computer for these motors. 86-89 got different ones. I just emailed them back asking if thats the reason she wont run. Anyone know? Thanks again for all of your help so far guys!

 

Couple of items:

The VATs issue will prevent the starter from turning over the engine. But will not affect it from starting (no VATs in '85).

Most likely the '85 ECM and an '87 ECM will be wired differently. Which means if the harness is for an '87, then it is incorrect for the '85 ECM. OK, just checked the swap site. To use the '85 ECM with the '87 harness need to swap a handful of pins.

My 85 Z28 and EPROM Project

May be easier to get a '86-'89 ECM & MEMCAL.

RBob.

 

Check out RBob's stuff
1226870 is '86, probably not '87.
I Use the OEM 1227165 ECM that came in the '88 350TPI with a '89 Corvette calibration ARAP to run my 388, and to delete the cold start injector system.
If you're keeping the '87 TPI as is then you'll need the '87, or '88 memcal to run the cold start injector.

if you have to comply with emmissions testing, then the test used will be for whichever is newer, in your case the body. I know it's just a sniff test, but the requirements are tighter for a 92, in other words the '87 is allowed to pollute more than a '92.

 

Thanks again guys, I'll be makin a trip to the dealership this coming tuesday to pick up an 87' ECM, what is the memcal thing your talkin about? Ive heard of it but never gotten around to asking what it really is. As for emmissions, come January pre-95 only has a visual check to make sure there is a cat, nothing else, thanks for the info though, I'll have to keep that in mind

 

The memcal is the chip inside the computer itself, and you'll need it for the new computer that you get.
I would take the chip with you and have them run the # on it to make sure that its the right one for what you are doing.

 

He just said he had a different ECM . There is no more VATS involved.


So can you even get the fuel pump to prime ? Is the coil getting power?

 

If the motor is an 87', the car is a 92' and the computer is an 85', would the be any trace of VATS at all? This stupid SECURITY light is really throwin me off...The Painless harness has a wire for the vats system, but I capped it and stored it...I had the fuel pump priming, but I made a dumb mistake and had my plug wires all goofy, got that right, then it decided to stop priming alltogether. Checked the fuse, it was fine. I don't understand how it would have already gone out on me, cuz I seriously put that in a few days ago, brand new stock pump... I haven't checked the coil, but there is one wire from the painless harness labled IGNITION... from the coil I guess??? it has to be hooked up to a 12v fused power source, and forgive me for my electrical ignorance, but I don't know what I'm supposed to do here, do I need to make a trip to the Zone and get a connector or somthin... apologies for completely forgetting to mention that when I started the thread...

 

The security light is part of the '92 VATS system, that doesn't go away just because you put in an older ECM without VATS.
The VATS system isn't in the ECM, it's a hidden stand-alone module that directly disables the starter, and commands the ECM to disable the injector drivers.
With the '85 Chip there's no disabling the injectors, but the VATS module can still disable the starter, unless you've bypassed that as well, but from what you've posted I doubt that.

If you decide to use a late model MEMCAL i.e. '88, or '89 from a Dealer be sure to have the VATS option disabled.

I would bypass the starter disable relay. Getting it to trun over is your first priority.

 

I had it turning over, why would it just randomly decide to stop and give me the security light after I've been able to turn it over for so long???

 

That's all it was doing - cranking, so get it back to that level, the VATS is just a distraction from the main goal which is to get it running.

Buy a remote starter trigger switch, and use it to test the starter (it's a good investment, about $10, trust me it has other uses.)

If it cranks with the Remote-Trigger, then either a fusable resistor that feeds the starter has blown, or the starter-enable relay is bad, and or the VATS module has disabled it, but don't count out a bad starter.

 

But you say ....




All you need is the memcal with VATS disabled. So yes it does go away with going to a different ECM ...or memcal. Kinda like you said in the bottom part fo your post

 

At this point in time he has an VATSless '85 ECM, he also has an active '92 VATS system which has set the Security light which means a VATS failure has occured and the injectors (moot point) and starter enable-relay have been disabled, but only temporary (about 4 minutes,) but as long as the Security light is on the engine must start, or the starter will be disabled again, that's why I said bypass it for now and get on with solving the no-start condition.
Later he can decide whether to completely disable the '92 VATS, or enable it.

 

i know this may sound stupid but did you check your oil presure switch, i know it wont run without it

 

Ok, got the fuel pump problem sorted out, shes priming now... and yes it was stupid but i didnt have the oil pressure switch hooked up I completely overlooked it... its wierd though, with the painless harness it has two terminals at the ends of the wires but no connectors... what am I supposed to do with this? They provided a connector but it doesnt fit the connector on the motor

 

well i work at napa autoparts and i know that some of our sensors come with plugins for an option, now if is dosent i know that you can go with an oil presure switch from another vehicl, one that dose come with the conector, all it dose is compleet your fuel pump curict. of you want to run the engine right away just to hear it run i know that you can cross bouth wires and make it direst, but this will run your pump at all times

 

So is it turning over now?
If so what did you do?
Security light still on?
Did you get a chip as well? Which one?

I couldn't find a harness part #68460 on the Painless Website, but all the TPI installation manuals have the following note about the oil pressure switch.
I know GM changed the pump wiring as early as '87 so that the Oil pressure switch is just a backup for the fuel pump relay, and doesn't act as a kill switch if the engine loses oil pressure.
The manual also states that the kit provides adapters for the type of oil pressure switch you have, or you can replace it with one that will fit the Painless connectors.

Painless installation note:
An oil pressure SWITCH must be used with this harness. DO NOT
BYPASS THE OIL PRESSURE SWITCH WIRES.If you are using an oil pressure switch that has two or three small pins
surrounded by a plastic collar for an electrical connection, an adaptor is
in the kit.
Note: The oil pressure switch wires are designed to be connected to an oil pressure
switch, not the oil pressure sending unit. An oil pressure sending unit is for a gauge or an
indicator light and will only have one terminal on the top. The stock oil pressure switch
is cigar shaped and has three terminals. If you wish to use the stock oil pressure switch
then you will use the oil pressure switch adapter included with this kit. On the oil
pressure switch adapter there are two wires that match the wire colors coming from our
harness and there is also an extra wire.
The extra wire is for the factory oil pressure gauge or indicator light, depending on what
the switch was originally designed for. You may also obtain a smaller oil pressure switch
if you have clearance problems with the original oil pressure switch. This type of switch
has two male connectors that will plug directly into the harness.

 

No, its not turning over now and my security light is on still... I didn't end up going to the dealer cuz Hawks has ECM's for $50 bucks. I was gonna order a prom from TPI Parts to go along with that. Wouldn't that pretty well take care of it besides the oil pressure switch, I fixed that last night...

 

The VATS is a distraction. Buy a simple push button switch and directly engage the starter. Now your cranking, and dont have the wait (Unless you got a lot of time to look at the engine instead of troubleshooting the thing).

 

I've swap a 305TBI for a 350 TPI engines with factory harnesses and you have to swap the fuel pump aswell. If going from TBI to TPI. TBI pressure is about 9-13 psi
TPI systems operate at a much higher PSI. If using a stand alone harness then hook up the pumps' relay and you should be good(from a fuel standpoint)
The easy way out is to use an external pump. Dont event have to drop the tank. The external pump will just suck fuel through the old TBI pump. Be sure to use a dedicated relay just for fuel pump to prevent shortage in voltage for good consistant pump operation instead of just giving it 12v.

Hope that helps....

 

I have the fuel pump issue sorted out, there was a wire from the coil I didnt have hooked up to a 12v fused source... so thats taken care of, I'm just stuck with the stupid SECURITY light still and it not turning over. I have a remote starter, I just have been super busy lately and haven't had the time to get out into the garage in awhile(40 hours a week at work and I'm still a Junior, so schools important too)

 

Ok, finally got around to checking the starter today. Hooked the remote start up and tried it... all it did was spin. It wasn't even hookin up to the flywheel at all, looks like I'm makin a trip to the damn Zone...

 

If you haven't bought another starter, check for 12volts (hot at all times) at the starter's solenoid terminal (B,) applying the remote switch to the solenoid terminal (S) when there's no 12volts at the B terminal will only engage the starter motor. Check the fusable links located at that same terminal.

If all power is OK pull the starter and have it tested, if it's bad have them test the new starter as well before you make the cash register go "Cha-ching."

 

Ok man, will do... got some time today ill go ahead and take it up cuz there was no power at the b terminal at all

 

Starter may test good.
No power at the B terminal means a fusable link is fried, fusable wire burnt through and now there's no connection, so your starter my still be good, use the remote switch to jumper directly to the B terminal and turn the ignition while holding the trigger closed then the starter should work, if it does you'll need to replace all the fusable links that are burnt.

Good luck

 

Thanks man, ill keep that in mind, my time ended up gettin cut short so I wasn't able to yank the starter or test it... good thing thanksgiving break is this coming week...