350 TBI conversion help (1 Viewer)

[Alz Toy]

Thanks guys I really appreciate the input!! About the VSS, I have done a lot of research on this, even bought a VSS from JTR and ended up returning it due to the requirement of a reluctor ring for my year which is NOT even available yet and is a custom machined unit that they are working on. I agree if you are running a automatic tranny a VSS may be required for accurate shifting and performance. My setup would also require a VSS buffer which is a another story, again this is all fine and good IF you are running an AT. I will remove the TBI and take a look at it, I think it could use a kit anyhow.. I should be getting this on the road in the next week or two and will update this post as to the results.. One other thing about the ECM, I have checked quite a few resources on chips and it seems that to get a chip burned to eliminate the AT tranny codes and VSS will cost me $170.00 I think I will see how things go with the stock program and put the money into obtaining the equipment to program and modify my own chip, saving me lots of money and time in the long run..

Time to visit Moates.net for tuning tools. With an OB1 computer, its basically a check/uncheck the box deal for VSS, etc using Tuner Pro RT. You probley know this allready.

 

[lehiguy]

I've been running for years with no VSS, had it deleted along with the EGR. Don't overlook the basics, like cap, rotor, plugs and wires. Sometimes a while with the battery disconnected is just what you need to go back into block learning mode. Here's my shameless plug; www.tbichips.com Great site, great guy, stunning performance out of TBI motors. I grin ear to ear every time I drive the beast.

 

[jkirk]

I'm having a problem finding a way to start a new thread on this site so I will reply to this one.

I am putting 1990 GM TBI system on a 1965 chry 273. When I turn on the Key the pumps start and injectors start pulsing fuel the pump doesn't shut off after 1 min this with out cranking the engine over.

 

[handcannon]

jkirk

Scroll your computor all the way to the top of the page and keep it there. Now, if you look down towards the bottom of the screen (not moving anything on the screen) you will see a yellow horizontal band. In this band on the left side will be written: "Threads in Forum: Hardcore Corner". Just above "Threads in Forum" will be a grey button with "New Thread" in it. Click on this button and you will go to a page that will let you start your new thread.

Welcome to Mud!!!! You have come to the best forum and, in my opinion, the best part of the forum for this kind of info. I don't post much here, just lurk. There are some awsome guys here with tons of knowledge and the willingness to share that knowledge.

Don

PS -- Mods may want to help this noob, move his post, and get a thread started so he will get maximum exposure for his question.

 

[jkirk]

new thread not on screen

don't see it at all

 

[jkirk]

The Dist wires from the 86 electronic Chry dist were in the wrong positions on the 7 pin GM ing module. Swapped the wires injectors stopped pulsing the engine started and ran much better than the carb ever did. Still need to connect Knock sensor, and get O2 sensors bosses installed and connected.

The GMC used a hot fuel module to limit pump power during ko and of course I didn't get that from that truck at the time.

 

[jkirk]

86 Chry Electronic dist, 88 Dodge van 75 Amp denso Alt, 1990 GMC Throttle Body, ECM, ing module, sensors, wiring harness, fuel pump high pressure Carter P5001 20 PSI 50GPH, Low pressure Fuel Pump Airtex E8090 5-9 PSI 30GPH, homemade fuel surge tank Installed on 1965 Barracuda 273 auto

 

[PhatFJ]

Thread update

Ok, so I made progress in a couple areas. First off, the biggest change is , I went ahead and got the EBL/ECM. For those of you who don't know what this is, it is an ECM that has it's own built in flash unit, all your ECM sensors, parameters, and performance are displayed in a WUD (What's Up Display). Changes are made to your ECM through a companion program called TunerPro. There you can modify or change any Bin or program then update it to your ECM through the EBL flash. Anyhow, I have eliminated the VSS for now, I can use a VSS if I want now due to this ECM not needing the Reluctor ring as part of the VSS circuit.. My knock sensor problem is solved, also with this ECM I needed to use the Knock Filter (which was built into my old PCM) so I am not getting any Knock codes .. I am however still dealing with this SURGING at idle. I have checked for vacuum leaks: none, replaced the ignition module, took off the TBI: cleaned it and put new gaskets on, pulled the EGR valve: tested it, checked the ports for buildup, reinstalled with new gasket, changed the MAP sensor, Fuel pressure does not very from 12psi, the only change from the stock motor are the block hugger headers. Now here is the weird thing, when I pull the timing advance connector, it smooths out but the O2's go through the roof , also when I pull off the vacuum control from the break booster it smooths out .. I am thinking that there may be somthing I can change in the ECM, either timing advance at idle ar maybe adjust the rich/lean setting at idle.. I have searched hours and this seems to be a common problem with MANY different resolutions. Any ideas are GREATLY appreciated....

Thanks!!! Phat

Oh and jkirk start your own threat man,

 

[Bug Gut]

while the engine is at idle the two mose important things are the running fuel pressure and the ignition timing. the best fuel pressure is 15 psi. if it drops down below 12 psi the mixture starts struggle. The ignition should be set at 0 degs at idle with the EST connector disconnected, this is a tan wire with a black tracer somewhere near the ECM, but the running ideal is about 2 degs advanced. Check the timing while its surging and see if the timing is moving causing the surge. The MAP sensor changes the mixture and compinsates for altitude, as the engine load changes the ecm will enrich the mixture

 

[Bug Gut]

after reading your last post I figured that the o2 might be cooling off with the headers, I would wrap the headers on the side that your o2. I also noted that when you pulll off the brake feed hose to the booster your o2 does odd things, your booster should be holding vac and not allowing air flow. you might have a brake booster failure.

 

[PhatFJ]

while the engine is at idle the two mose important things are the running fuel pressure and the ignition timing. the best fuel pressure is 15 psi. if it drops down below 12 psi the mixture starts struggle. The ignition should be set at 0 degs at idle with the EST connector disconnected, this is a tan wire with a black tracer somewhere near the ECM, but the running ideal is about 2 degs advanced. Check the timing while its surging and see if the timing is moving causing the surge. The MAP sensor changes the mixture and compinsates for altitude, as the engine load changes the ecm will enrich the mixture

Thanks, the timing is spot on at 0* with EXT disconected, the ECM however is advancing WAY to farr at idle. I am watching the o2 senser at idle and the only time it goes crazy is when I disconnect the EST and that is when it drops back to Zero and idles fine.. As farr as the Booster goes it is sealed fine, it is only when I disconnect it and allow vaccum in that idle smooths out,, I know weird!! I would have thought it would lean out and die immediatly.. I took it out yesterday and am doing what is called VM learn with the EBL system, this is where the system learns how you drive and what is required, adjusts the paramiters and then you can flash to the ECM the changes made.. So farr it is going well, I will play with the timing at idle later today, I think this is the culprate with the surge.. I will let you know what I find out..

When you say wrap the headers, what do you wrap them with?

Thanks again!! Phat

 

[Elbert]

what is the fuel pressure? Do you have any popping back through the throttle body, and are you sure your timing is good at number 1 cylinder. I dont't follow ECM is advancing a lot at idle. That normally happens if you are off your base timing setup, then the ECM just tags on on top of whay you have set. And end result is running like crap. You dont' have issue with the timing chain?

Seems like if you have major vaccum leak your idle would be crap? Any you have no trouble codes?

 

[lehiguy]

after reading your last post I figured that the o2 might be cooling off with the headers, I would wrap the headers on the side that your o2. I also noted that when you pulll off the brake feed hose to the booster your o2 does odd things, your booster should be holding vac and not allowing air flow. you might have a brake booster failure.

Wrapped headers rust as a general rule. A pre-heated O2 sensor is a good investment with or without headers.