Quote: Originally Posted by animute I don't know if this sounds to simple but this sounds like partially clogged fuel filter, check under the car. Thats a good idea....But I think WileE pretty much changed all that when he first started this thread........Cudos to WileE! If he did change it, it should be listed under posts 1-5, I think! Edit: I just read some of it and he doesn't say he change the fuel filter, but he did say that"Cranking gives a constant 41 lbs of pressure."

Hello all. Nope. Didn't change the fuel filter on mine because I had good pressure at the fuel rail. My problem was the magnetic pickup on the distributor shaft being rusted enough that forcing the engine to fire with starter fluid evidently scuffed the pickup enough to run for a while. But then it would eventually rust up again from just the moisture in the atmosphere if I let the car sit for a couple of days. A total new OEM type distributor R&R solved my start problem.

Been dealing with hesitation off a stop sign. Got the TPS replaced and adjusted but had to bend the idle seat on the throttle air valve cable side since my 91 does not have an adjustable TPS. Doesn't run rich now but still has that slight hesitation that experienced drivers can just tickle the gas pedal through but a novice like my granddaughter wouldn't know how to.

A group of six corvette owners my son spent the Daytona 500 race in a basement partying with convinced my son (father of my granddaugther getting this car) that I needed to replace the injectors. He was willing the pay the cost so I ordered a matched flow set from FuelInjectorConnection and researched the repair.

To the TGC member who posted on the Injector removal thread that it was a two hour job my hat is off to you, sir. You must be one heck of a mechanic. I'm no novice and it took me four hours to just get the fuel rail OFF! And it takes removing the alternator and the thermostat housing in addition to what our fellow forum members and Chiltons has to say about it. Unless, of course, you have a factory fresh car with no stubborn fuel lines or bolts. Man those lower TPI runner bolts were a pain to find and get out. I'm really looking forward to trying to line up the new gaskets when I put this beast back together.

We'll see if the new injectors solve our hesitation problem. But it's going to be a few days to get there.

And did I mention in another post that the jerking feeling at 40 mph has been diagnosed? It's the 700R4 tranny trying to decide if it wants to stay in overdrive or shift back down to third. It was "supposedly" overhauled 85,000 miles ago. Fresh fluid flush didn't resolve it but I couldn't find anyone around here that would pull the filter and change the fluid the right way for less than $200. So I'll reserve judgement until it gets warmer and I can do the filter change myself the proper way.

COME ON SPRING!

Just checking, did you try adjust the TV cable?

No I didn't try adjusting the TV cable. My reception of the Olympics has been fine. Okay, bad joke. I'll get the manual out and see if I can do that. Thanks for the suggestion.

Use the pedal instead of turning the throttle by hand to WOT . The pedal may not open the TB as much as opening it by hand. If you have a mat that limits the pedal travel don't remove it, remember it's not a Toyota.

To any user who has given advice to WileECoyotesr, he was fixing my car, and its now running the way its supposed to, THANKS!

It finally all came together. The hesitation problem was fully solved by installing a matched set of remain Bosch III injectors. The jerking at 37 to 40 mph was overcome by adjusting the TV cable as suggested so that the 700R4 is not indecisive about staying in overdrive. The granddaughter test drove the car again today and agrees it's totally awesome.

She doesn't know it but she'll find a big red bow on it tomorrow afternoon when she get's home from Volleyball.
Thank you all for helping make this little girls dream come true.

Oh by the way. I put one restriction on the deal with the girl. If she damages the car beyond economical repair I get what's left back. I'm praying I don't end up with that project.

as I am too, can't stand to see another perfectly good third gen cracked up :'(

quick question... what would cut fuel just after crank?
like this-


the ecm is cutting the pump off after start... i'm gonna check tomorrow and see if the regulator is bad, was told to kink the hose on the return side and see if pressure stayed ok...

oil pressure switch. I'd be more worried about that nasty rod knock you have there, but considering the way that thing sounds, i'd bet the two are linked

that's not a rod knock. this is a swap and the flywheel bolts rub the dust cover... the oil pressure switch is wired up right, i believe... when i jump it, the pump runs all the time(even with key off)

good, put a new oil pressure switch on it and wach her run

the switch is brand new. is there any way to test it?

maybe build pressure the check continuity?

that jumper the wires for thr switch (down by the oil filter) to make the pump run constantly, THEN try running it, if the engine stays running then you either wired it wrong, or you got a bad switch out of the box, if its a duralast switch it wouldnlt surprise me one bit

nah, dude, the switch is a factory s10 switch, the guts are the same principle... its just a 3 wire... (one for the gauge) when the switch is jumped the pump runs constantly until the truck starts running, then the computer takes over and kills it, setting no codes... i pulled a 42 and 54 when i unplugged the relay(while setting the timing) but it cranks up, then the pump cuts off... while the pressure is still good, i can rev the engine to about 2500 then it shuts off... FPR maybe bypassing too much fuel and i just can't hear the pump running? should i put a test light inline with the fuel pump connector to see if it's still running(when cranked)?

or unplug the relay and jump the switch maybe?

ok what car and engine are we talking here? the ECM in a camaro does NOT controll the pump

it's a 85 tpi 305motor with a 88 tpi ecm. my diagrams here say:
ecm A1- fuel pump relay
ecm B2- fuel pump signal

put a test light inline and see what happens, the pump should run when there's oil pressure regardless of run state

if it doesn't?

..... is this a camaro or trans am ECM?

Hey there Buddy..... I didn't realize that the ECM's mattered which car they came from! Why is that???? Please explain!

camaros did not recieve VATS till 89, Tran ams got vats in late 87

Useful Info Regarding Relays:

*Fuel Pump relay: 12GA Orange, 16GA Orange, 12GA Tan w/white stripe, 16GA Black w/white stripe, 16GA Green w/white stripe (5 wires)

*MAF Power relay: 12GA Orange, 12GA Tan w/white stripe, 16GA Black w/white stripe, 16GA Blue(solid), 16GA Red (5 wires)

*MAF Burnoff relay: 2x 12GA Orange, 16GA Black(solid), 16GA Blue (4 wires)


Note: GA, refers to the GAUGE(thickness) of the wires used!!! Ex. 10-12GA is thick......16-20GA is a much thinner wire. The lower the # the thicker it is!

P.S. I am GUESSING at the size of wires, the sizes listed here MAY NOT BE 100% ACCURATE!!! I am comparing the relay wires to my own supply of wires in my garage.

would VATS even matter in my case? the engine will start...

in any case, i matched the prom #'s
1988 MAF 305 tpi 5 speed
AKFU 2417 2371 5 spd man 3.08 Fed F

Sorry to bud in but can the magnetic pickup in the distributor be cleaned? Mines very rusty and the car doesn't start. Also, is there a ESC module as well that may affect start up?

UPDATE: LS7Roc is back on the road. From what I understand, it turned out to be his pickup coil and a timing issue!

Had the same problem with mine and it was the key. The pellet on the key was worn so it would sometimes not make a connection causing the security to kick in and disable the fuel system.

Now I need some advice. Lol. Okay... like many others who have posted abt their no start/failure to launch conditions, I too am experiencing the same situation. I have a 91 305 tbi. I start it and it cranks and fires but dies out after abt 2/3 seconds. like everyone else, I checked and replaced everything from the fuel pump up to the tbi and still nothing. I've been told that my injectors aren't firing and perhaps I have a bad ground wire or something. After reading the entire thread, I've decided to go ahead and change the distributor. But before I do so, thought I'd ask on your thoughts abt it. I had it running about a week and 1/2 ago but once I decided to change my IAC and fuel pressure regulator (because the idle was really high), my fuel pump went out and I replaced it, now I'm stuck with this start/die condition, I have no answer to.

Thanks in advance,

Thomas

Injectors on a TBI like a Carb's jets are easy to confirm if they're spraying fuel, just remove the TBI and look inside as someone cranks the engine.
Assuming no electrical problems they work or they don't. The Electronic Spark module supplies the ECM with a reference signal to fire the injectors so have that tested first.

Is it possible that the electronic spark module could be bad? If so, where is it so I can replace it.

Yes, it's possible, but don't just replace it have it checked at an auto parts store.

I have a 89 Camaro RS with the 305 TBI in it. It will crank and crank but will not start. Got it to start once with starting fluid but cant get it started again. When it fired it would just die. the VATS has the resistor so that doesnt seem to be the problem. so far we have replaced: fuel pump, pump relay, and ICM, the pickup coil tests at 792 ohms. the is power going to the injectors but still no pulse (checked it with a injector noid, and a tester light) is there any other problems that could be stopping the injectors from firing? i have a thread in the TBI section but i figure id post here to cuz theres been alot of good info

The VATS module can fail causing it to drop the fuel enable signal to the ECM. The start enable relay still works, just no injector pulse. Do you have spark? Have you ohm tested your injectors?

Hey CamaroZilla, can you update us please?!

never got it running and didnt want to start dumping tons of money into it so i sold it.

Awesome thread here guys, going to apply a few things I've found in here to my junk and see if we can get it up an running.

Hey guys, please take a look at what my car is doing. (click it for video)


There is a relay that clicks as the CEL goes on and off, maybe can hear if speakers are turned up.

91, L98, auto
I have ohmed the injectors and they were all 15 or 16 within 0.1 of each other, but I haven't gotten much further. My ICM is a few years old (duralast) and I have and MSD 6A with MSD coil, cap, and rotor. I can hear my pump prime, and if the CEL stops flashing she will start, but if it flashes, no luck.

When she does start she runs for a few minutes then just dies. for the most parts there have been no codes that I can get from it, but I believe it flashed a 33 during an episode the other day.

I haven't gotten very far down the list of things to try in this thread, but it seems to be a similar problem.

First, get all the codes..... we need to know what she(car ) is telling you......

I'll see if I can get anything else tomorrow after work. Whenever the CEL is flashing it will not give codes. And I haven't gotten anything but 12s since.

12 and 33 is all it will give. And it only gives a 33 after it is able to start.

Ok, I took the IAC out and cleaned it up, seemed like it idles a bit smoother, but nothing else is better. I tried to drive it and it stumbles for about a block and dies.

Another thing that I found out was that apparently the fans are not coming on and the car got pretty hot idling (230-240 maybe).

Related? The ECM failing?

Just a quick heads up for those who have replaced fuel pumps and still have no start...when I replaced my pump I accidentally reversed the two wires causing the pump to prime at key on engine off but instead of flowing fuel up towards the engine, all it was doing was running and swirling the gas in the tank. I dropped the tank and corrected the wires and after that it flowed correctly out of the tank and to the engine. Simple mistake but anyone can make it......

My first post. Have 92 rs 3.1 auto. will crank no start. Have read this long thread. Have read Vader's article on vats bypass , vats mod not in same place as his article. Anyone have a pic of this module. and location.