305 tbi starts , immediately stalls, runs good on 2nd start?

[95Noobie]

Your help is appreciated! I have the 3.73 gears so I guess there is an option to go to 4.11 but would have to find new setup for front and back and perhaps a whole front diff swap and a rear axle swap would be easier. But that can wait for now.

The annoying thing with my 'electronic' overdrive is that it tries to engage right at about 42 or 43 mph. The engine rpms drop too low and it lugs like crazy. I keep having to kick the gas to get it to pop out of 'overdrive' and back to '4th'. In another post we were discussing some type of interrupt switch in a wire (maybe to the brake signal wire?) but some where also saying that would keep converter unlocked and that would not be good for it.

sadly this transmission can't be 'tuned' in an obd1 truck. I guess if I LS swapped and added a obd2 port then perhaps it could be (I'm not sure I understand this but the transmission tuners I talk to can't talk to my transmission if I have obd1 port) If I could only change the rpms or speed at which it drops to the electronic overdrive to like 55mph or maybe 1700 rpms or higher that would help.

I agree, for now work on getting engine to run well and then learn to tow the few times we do in 3rd. (or work on extracting a little more HP out of a 305 if that is even reasonable or safe such as adding a different cam, working on better air intake, or some other similar thing)

I haven't heard from the tranny shop yet but anxiously waiting. Happy that the guy has lots of experience rebuilding and is willing to do the remove and replace for fairly reasonable.

I'll have a new fuel filter ready and easy to swap in.

I studied the underside of the injector mechanism and see various O rings and a gasket. The fuel pressure regulator likewise I can see the kit for cheap online and I don't mind swapping it out if someone recommends. Or is there a way to open it and clean or inspect it? It has a diaphragm and a spring inside I see?

I replaced the two grounds wires that connect to the passenger firewall area. I also removed, resanded the metal and reattached the one by the gas fill tube. If there is another one I missed I'm happy to do so.

I can't visually inspect the one that goes from the passenger sidewall to some spot between the center firewall and the 'back' of the engine. What a difficult spot to choose to ground something. I have no idea if that connector and connection is solid and also don't even know how to get to it while the engine is in.

thanks!

 

[docstoy]

The ground at the back goes to bellhousing bolt , grounds are very important on any electrical system and if bad enough will cause false readings or no operation same goes for wir terminals that don't have enough tension. If not wanting trans to shift into 4th/ tcc lockup, drive it 3 until you reach speed your comfortable with then move shifter to D. Yes think a 4 something was an option what's hurting you now is taller tires . Again good luck

 

[95Noobie]

Hope the tranny guy will be sure that ground is good since he will be unhooking it and reattaching it again.

Is there a list on the forum of ALDL or OBD1 scanners that do live data? I understand the old Red 2500 Snapon does? I thought the Innova 5512 did but once I bought it I found it only reads codes. It doesn't erase obd1 codes either which is disappointing.

I've read about computer programs with usb adapters or bluetooth adapters to ALDL and could go that route.

I also read that the Bosch 1300 will work with ALDL but I can't confirm if it gives live sensor data. Anyone know?

 

[docstoy]

Can't answer that question , I have gm tech 2 scanner

 

[docstoy]

Just looked search forums with data scanners looks like plenty of reading

 

[95Noobie]

I've searched and have been tricked by those who say they work with obd1 but then they don't specify if they do live reading of sensor data

 

[thinger2]

Yes, TBI and the fuel filter is new, but I know when we cut the old one out (cut it out due to corrosion so bad on the fittings) that pretty nasty rusty sludge came out of the old one. I have no idea condition of the inside of the tank or the age of the current fuel pump and sender. Judging by the rusty bolts and straps it has been in there a while.

I don't understand how a fuel line cleaner would add restriction but if that is the case it would be very simple now to replace the fuel filter again since I have repaired metal lines on both side of the filter (where someone had used rubber hoses to patch it in) and the fittings on the current fuel filter are brand new so easily removed.

I dropped off the truck tonight (much longer story) to get the transmission rebuilt. We were getting slow activation into reverse and slipping if trying to back up a slight grade. We were occasionally getting a hard shift between one/two but only if steady pressure on accelerator was holding rpms up before the shift. I debated finding a rebuilt one and putting it in but research showed that this transmission was unique in its attachment to the transfer case in the 1995 year and would be very hard to find that exact setup in a rebuild shop.

While it is on the hoist they will check transfer case, seals, and look for any unusual findings. I asked while the tranny was out to drop the oil pan and put a new gasket in since I think the slow drip off the bell housing of oil was coming from the leaking oil pan gasket.

Of course none of this relates to the new issue with the engine not appearing to pump enough fuel right at startup to keep running on the first try.

One other variable but hopefully it is not related, there are posts on this forum where a hard 1-2 shift was related to low power on one of the wires going to the ECM. The video shows very clearly the problem with the low voltage giving a higher than normal pressure build up and a hard 1-2 shift. I did swap my ECM computer and PROM using an exact match from a donor 1995 chevy. The truck ran normally after this switch for about 2 weeks so not sure that could still relate. I guess I could easily swap back to the original ECM or at least swap the PROM back as a troubleshooting step.

This project has been way more expensive and time consuming then every imagined. We have faced nearly every hurdle mentioned in this forum.

Assuming the rebuilt transmission will be solid for a long time and it goes well, I was toying with LS swap but the price tag is insane. Swapping a 350 TBI probably won't give much of a difference. I think we may just have to stick with the 305 for now and try to idealize its performance. The tranny shop guy has some history of doing a few LS swaps and he said before we go through the time and cost for limited improvements in power, (it is a 5.3L vs 5.0L displacement), he said our budget could more easily handle the simpler task of putting a slightly 'souped up' cam (he mentioned an RV cam). But that is only after we get the engine starting and running normally again.

I think the cruded up fuel tank is the problem.
You can buy a fuel pressue kit from harbor frieght that has the tbi adapter.
Oreillys also used to have a rental tool with the tbi adaptor. Just make sure you open the box and look to see if it is still there.
They are often times stolen.
If you have crap in your fuel lines when you take them apart, unless you somehow flush that tank or replace it,
You will have crap in your fuel lines again.
With a tbi adapter you can check fuel pressure going into the filter and pressure coming out of the filter.
I skip a step and only check pressure out and if it fails I replace the fuel filter and run it around the block untill it fails again and then check pressure OUT of the filter again.
If you have good pressure out on a new fuel filter and then you suddenly have bad pressure something is plugging your fuel filter.
While you are doing this you need to pay attention to fuel pump run time.
It should be something like 3 to 5 seconds before shutoff.
If you have reliable fuel pressure every time with a new fuel filter.
That means that everything from the filter back is good.
I think the crud made it all the way past your fuel filter and you should rebuild your tbi.
Pretty easy to do.
Dont let let the 350 boys tell you **** about it.
You can carb a bone stock 305 and set it up with a mild cam and get 300 horse easy.
Because in 5 litre hydroplane racing we have been doing this forever.
class rules are bone stock internals no boring no balancing all parts need to off the shelf gm parts.
We get 1 cam to use and 1 aluminum intake to use.
This is the part that kinda cracks me up a bit when people claim that you cant make 300 horse out of a 305.
Yes you ******* can make 300 out of a bone stock gm 305.
Because of class rules weve been doing it since the 305 came out.
The 5 litre boats were a classification that was set up to try to even out the sport and try to make it more about the drivers and the teams instead of about how much money you had.
That is why you could only run stock gm internals.
We got into boat racing after my Dad hired my uncle to pack the chutes on his drag rail based upon my the theory that my uncle had been a parachute guy in the army.
And he did pack that chute.
He didnt attach it to the rail.
So Dad did about a 9 second run on nitro which was pretty ******* fast back then and popped the chute and it fell on the track and he went all the way into the gravel runout at the old Puyallup raceway.
And broke his back.
Again.
When he was able to gimp around again they got in a big fight and mom threw his drag racing trophy right through the front ******* window and told him he couldnt race cars anymore.
Thats how we got into hydroplane racing.
Mom didnt say he couldnt race boats.

 

[Schurkey]

As said, there's dozens of threads about scan tools. A search of the forums will reveal much info.

Here's one, although not exactly what you're looking for.

Confirmed brake bleeding scan tools

Can we get a list together of scan tools that have been confirmed to activate the ABS modules? I’ve emailed every Chinese scan tool maker I can think of and all have said no, but I know that there are some out there.

www.gmt400.com

 

[GoToGuy]

You want the trans to stop shift hunting back and forth, up and down. It is recommended for around town , stop and go shopping non highway speeds. Instead of driving in " D " , drive in " 3 " . That's what I do around town , shopping stops, speeds 45 and less. This prevents it upshifting when you let of the throttle, or hunting up and down.
The original owners handbook references it.

 

[95Noobie]

THinger2 your write up is great and I love to hear the history and what can be done with the 305!! Thanks for the encouragement.

I can easily replace fuel filter but before I do a lot of testing it would seem logical to try to flush the tank. I can let all the gas drain out from the line right before it hits the filter. But how do you 'flush it'? Just keep adding a couple gallons of gas, slosh around the block, drain etc?

I also don't know how to tell fuel pump 'on time' You can hear it? I can't hear my pump like I can in my 2003 suburban. If it is on longer than few seconds that means it is working against an obstruction?

I have parts ordered to open the fuel pressure regulator or replace it. I"m not sure if the gaskets will come with the regulator so I may need to order a gasket kit as well. Right now I'm not set up to replace the fuel injectors but I can inspect the spray pattern and save that for a 2nd step.