55mikey55

iTrader: (1)

i'm swapping an 85 tpi 305 into my s10... tomorrow i'm gonna crank it up for the first time. i bought an 88 305 tpi 5 speed prom/calpak from one of the dudes on this site... i don't know if it had VATS or not... now, i have no real way to know if it's gonna start tomorrow. if there is no VATS signal, does it disable the starter? or will it just not crank??? any help/thoughts will be greatly appreciated

HCR13

iTrader: (5)

I believe vats cuts the fuel. So it will probably crank but not start...

55mikey55

iTrader: (1)

does VATS kill the injectors? is there any way to tell if vats is enabled with a test light or anything? if not it's gonna look like timing to me and i'll probably **** it up... before it ever starts...

if i post my chip #s can anybody tell me whether or not vats is enabled...?

HCR13

iTrader: (5)

well, you said it started before the turbo install? with the same key? if so, then it should start again after the turbo install. Keep cranking and see if you smell gasoline (in the engine bay). If so, verify if you have spark...

five7kid

iTrader: (14)

There is no need to guess.

https://www.thirdgen.org/vats

https://www.thirdgen.org/vats_passkey_system

camaronewbie

VATS won't let it crank at all, so the starter won't turn at all if the VATS is engaged.

55mikey55

iTrader: (1)

i have no VATS module. this is a swap. 305 is in my s10. i'm gonna have to buy a vats defeater/bypass module if it doesn't crank...

camaronewbie

I understand - I'm just saying, when the time comes, if it cranks but doesn't start, then it's NOT VATS, it's something else. If it doesn't crank at all, then VATS would be a possible reason.

Stephen

iTrader: (12)

If you don't have a VATS module, then there is nothing to bypass.

It'll start if it is hooked up right, no worried.

Maverick H1L

iTrader: (8)

You don't have to worry about it... VATS didn't come into play until 89...

If the MEMCAL had VATS, the engine would crank over all day but you wouldn't even get a burp out of it.

55mikey55

iTrader: (1)

ok. is VATS the issue when:
the truck will crank but not start. this morning it would kick over, but now, it won't. it tried to start earlier today, but it died when i touched the gas pedal. every time the ignition is cut off, the fuel pump engages. it's kind of cool outside here, about 68, so would i have flooded it maybe? i'm new to this F.I. stuff, thought it would be cool to have for eliminating hard starts...lol
so, i'm trying to set the timing, the motor cranks, then cuts off, it may have run for 2 sec. i have turned the distributor any which way possible...it will go from pointing at the coil, to just past perpendicular with the firewall...

some1 please help

Stephen

iTrader: (12)

VATS did not exist in 88 or 85 & VATS uses a completely separate box to control it, so you don't have any VATS to worry about.

To set you timing, you need to adjust it manually with the engine off (like starting a brand new engine for the first time) to where it should be so the engine can be started, then adjusted with a timing light from there. If you have been twisting the dizzy by hand blindly, you are probably just too far off, for the engine to even start.

55mikey55

iTrader: (1)

ok... corect me if i'm wrong, but these are the steps taken so far...

1. unplug the "set timing" connector (tan wire/black stripe i think...its the connector that's only 1 wire and it's wired inside the truck)
2. loosen the distributor
3. turn the crank until the engine is at 0 degrees
4. turn the distributor until the #1 post on the distributor is pointing at the #1 spark plug
5. crank the engine
6. truck does not start...

i'm getting fuel, and fire; the MAF intake hose is disconnected (air filter side)

are there any pre-startup things that need to be done to a tpi motor that is different from tbi/carb?

HELP!

Maverick H1L

iTrader: (8)

Pull the driver's side valve cover. When the 2 valves towards the front of the engine (#1 cylinder) are fully closed, then line up the damper with the timing mark and go from there. Just because you think the dizzy is in the right spot, it may not be, and this is the only way to make sure you have the right cylinder set up for TDC.

55mikey55

iTrader: (1)

ok, does the distributor need to be lined up with the center of the cylinder, or does it need to be lined up with the spark plug?

this morning when i got it to crank, the distributor was turned about 45 degrees counter clockwise. if this helps any...

Maverick H1L

iTrader: (8)

The dizzy can point any way you want it to, provided you put the #1 plug wire where the rotor points when the #1 cylinder is at TDC.

55mikey55

iTrader: (1)

ok...so cap is going to come off tomorrow morning... thanks dude. it never really dawned on me why the post always had to point at cyl #1...lol when i was in school my instructor would always tell me that and i was always puzzled why if the dist spins free does it point to the cylinder...but, i know now ...thanks dude. dizzy points wherever. rotor has to point to #1 on cap when cyl #1 is at TDC. timing mark is 0

Maverick H1L

iTrader: (8)

That's the general rule. However, on those TV shows such as MuscleCar or such, have you seen them just toss the dizzy in place? That's so that during the break they can find out where the #1 plug wire is supposed to be and fix it. Yes, generally, you want the #1 cap terminal facing the #1 cylinder, but you don't necessarily HAVE to do it this way.

55mikey55

iTrader: (1)

update for today:
it cranked up... then it shut off by itself. then i went back to turning the dizzy back and forth to get it to try to crank, but nothing... FP still runs, but no cranky... i killed the battery then charged it back twice, and called it a day. i'm gonna go check the fuses first thing tomorrow, then if there are no problems there, I'm going to rewire the alternator and ecm IGN(+) wires (i think i wired them backwards)... plus, i'm forced with a dilemma... i just thought of this... if i have my injectors wired to my ecm(+ IGN) wire, and they have the same 10A fuse... [ecm has 10A (in the fuse panel) and injectors have their own (inline 10A) wired downstream from (ecm side) the fuse box]...will this work? or do i need a bigger fuse in the fuse box and put a inline on the ecm side?
<-that's how it is now...

55mikey55

iTrader: (1)

the reason i suspected the alt being wired wrong is cause it hums when the key is turned to "run". not very loud, just enough to notice it

Maverick H1L

iTrader: (8)

There's a term used on some repair orders that is used when someone comes in with a ridiculous complaint, that is a play on words, that applies here. "Spodadodat".

Second, you can't run both sets of injectors AND the ECM off of the IGN fuse. In these cars, stock, each bank of fuel injectors has its own 10A fuse. I would suggest that if you're going to run the system that way you either find a second ignition on power source or run the fuel injectors off of or wire in relays so you don't blow that single 10A fuse.

55mikey55

iTrader: (1)

i was just wondering if this was some knd of feedback through the alternator, where the alternator needs a signal to run, off of a higher amperage fuse, but the ecm runs from lower amperages

55mikey55

iTrader: (1)

would this work better?


relays for injectors and e-fan, with no current draw from the ecm, but, on with the ignition...
edit: oops, the fan is wired wrong... relay "b" should terminate at the ecm, but in rleay "C" the ecm C1 pin will feed the (+) side of the relay

Maverick H1L

iTrader: (8)

There are times when I wish I had a mouse instead of a touchpad... What you have there basically means that none of the relays, and the ECM, won't have any power because most of the voltage is used by the first relay, so none will work. You want to connect each relay into parallel with the ECM also in parallel.

Basically, you want the ignition power source coming into each relay at terminal 85, which is the coil power supply. Relay terminals 86 (coil ground) go straight to ground. Terminals 30 (supply power) come from the battery. Terminals 87 (load feed) go to the injectors or whatever load is on the circuit. Also, the ignition power source comes into the ECM. Do not use terminal 87a (constant on until relay is switched) on any of the relays. Remove it.

If you don't know which terminal is which, go and buy a couple of aftermarket square relays and connectors. The terminals will be labeled.

:edit: Oh, and the ECM NEVER powers a device, well, at least very rarely. The ECM will almost always GROUND a device to switch it on and off so as to avoid high currents that could cause damage.

55mikey55

iTrader: (1)

better?

55mikey55

iTrader: (1)

wait i think i remember what you're talking about... hang on...painting lol

Maverick H1L

iTrader: (8)

You got it right that time. Since the ECM is controlling the ground on the fan relay, the others connect either to the body or to a bus bar that is grounded by a wire or bolted to the body somehow.

55mikey55

iTrader: (1)

like that

55mikey55

iTrader: (1)

the ground for the relay c has to be from the fan controller in the ecm... i can switch it since it's easier...(don't know how to wire it in series and have 2 different pins...)

Maverick H1L

iTrader: (8)

Fan relay won't work on that one unless the switch is turned on... Run the switch in parallel off of the ECM wire, to ground as well, and that will do. Keep everything the same as the second picture except for that switch if you're going to use one.

55mikey55

iTrader: (1)

so put the switch in the ground instead of on the fuse side?

Maverick H1L

iTrader: (8)

Yes. Run the fan relay coil ground wire to both the switch and the ECM, and wire the other side of the fan switch to ground. That way, if the engine isn't hot enough to run the fan (235*F), you can turn the fan on any time you want. If you were to do it the other way, like you had in your last picture, you would still have to wait for the ECM to ground the relay before the fan would turn on.

55mikey55

iTrader: (1)

or this

or

and wire the ecm instead of the ground(therm switch)

Maverick H1L

iTrader: (8)

Okay. The way the radiator fan and alternator circuits work is as follows in the F-body: Both have the same ignition feed, through the C/H FAN fuse (20A). The fuse feeds into the alternator's sensing wire at terminal F, a BROWN/WHITE wire. This same wire also feeds power to the power side of the coolant fan relay coil.

The coolant fan relay receives direct battery feed to one side of the switch. The relay switches this battery feed directly to the fan motor. The motor grounds to the body. As stated above, the same fuse powering the fan relay coil also powers the alternator. The ECM controls the ground side of the relay, which is also where you want your auxillary switch.

Depending on how many ignition-controlled circuits your truck has, you may need to run another relay. However, if your alternator is currently working, you can probably get away with running the relays as you have in the second picture, since each relay coil uses around only .5A, and don't rewire the alternator unless its F and/or L terminals are hooked to a constant power source (which needs to be ignition switched or the alternator will never turn off).

55mikey55

iTrader: (1)

sorry for being a pain, but could you use post #'s instead of 1 or 2?

55mikey55

iTrader: (1)

BTW truck ign circuits are as follows...
inst cluster, o2 sens, alternator, a/c comp relay- 1st
ecm, esc, fuel injectors (2), vac regulator- 2nd

oh yeah, the truck didn't start the other day...
could this be due to the injectors all being on the same circuit? and they are wired inline with the ecm on the ign + wire

Maverick H1L

iTrader: (8)

Are you going to keep the A/C? If not, then wire in the coolant fan relay feeding off of that circuit for the coil power. You'll be fine wiring in the relays to the ECM power circuit as in post #25.

And yes, the no start could be caused by the fact that the injectors aren't wired right, and drawing too much current for the fuse to handle along with the ECM.

55mikey55

iTrader: (1)

alright thanks... i'll post pics when it's done. i got about an hour of pulling wire and wiring relays in today, i'll finish it tomorrow if it doesn't snow

Maverick H1L

iTrader: (8)

Best of luck.

55mikey55

iTrader: (1)

alright. it worked... now the relays click with the key on, but still, no start. i looked on chevythunder.com and got a flow chart, and it says i have an ignition problem... but i have full spark on all cylinders... at least at the wires... i pulled my injectors and put in new o-rings, and will get the plenum and all put on today... how important is it to lube the o-rings for a reinstall? i'm gonna put it all together and give it a little shot of ether and see what happens... BTW, will the engine run with the MAF's air cleaner side intake taken off?

Maverick H1L

iTrader: (8)

It's not absolutely necessary to lube the injector o-rings before installation, but you'll have a harder time removing them later if you don't, and it's almost a guarantee you'll need to replace the rings when you remove them. If you have other problems with them, you could destroy the rings before you get the engine running.

Yes, the engine will run without an air cleaner. Just make sure you don't have any cracks or breaks between the MAF and the throttle body, as this screws up the readings.

55mikey55

iTrader: (1)

i don't have anything in front of the MAF, except a radiator right now...lol

55mikey55

iTrader: (1)

ok, the truck won't run for more than 6 seconds... what sends the signal to the ecm to turn the f/p on?

Maverick H1L

iTrader: (8)

Check the wiring to the fuel pump relay and the oil pressure switch. If the fuel pump runs when the key is first turned "On" for 2 seconds, the fuel pump relay is doing its job. If the oil pressure sensor is working, the fuel pump should run until the engine is shut off and oil pressure is lost. Check the fuel pressure at the fuel rail with a pressure gauge when the engine starts. It should hold steady at about 42 PSI when running (anywhere between 37 and 47 PSI).

Did you put in a fuel pump matching the engine? If not, you're starving the engine for fuel and that could lead to major problems (detonation due to a lean condition does BAD things to an engine).

55mikey55

iTrader: (1)

pressure starts out good at 45, then bleeds off to 25. i bought a puel pump for a 88 tpi, but it came from china...i'm thinking about just buying a new one from the auto parts store, but i want a high flow pump...

Maverick H1L

iTrader: (8)

Do something about that pump before doing anything else. 25 PSI isn't enough to run the V8. When the pressure bleeds off, is this with the engine running or not?

55mikey55

iTrader: (1)

the pressure bleeds down to 25 while running...then it shuts off.

should i try straight wiring the pump, like to a switch? turn the switch on, then see if it stays cranked? it sounds to me like the pump just quits after initial prime... correct me if i'm wrong, but shouldn't the pump shut off when it reaches pressure? and shouldn't it run constantly while the engine is running

BTW do you have AIM?

Maverick H1L

iTrader: (8)

Has the wiring to the f/p relay and/or the oil pressure switch been modified?

55mikey55

iTrader: (1)

i wired it to work with my 3-wire pressure switch

Maverick H1L

iTrader: (8)

Can you illustrate this?