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Discussion Starter · #1 ·
Well, got a call from the shop that had my 57 saying they were working on it and asked what was wrong with it....again. Yeah it was on of those shops.....lol...but it was ok, I have moded the heck out of the car. Anyways, after that call they called back (because I told them to call me after they hooked it up to the computer and before they touched her) an said that there was a couple of issues but nothing major. First was the starting issue, they said that they had plenty of fuel pressure but the pressure would bleed out of the TBI when the motor was shut off. They clamped the return line to test and said the problem was the pressure regulator in the TBI's return side. Any thoughts on that one? Need to research if they are made to do that or if the pressure regulator has gone bad and needs replaced.
Next was a timing issue. This is were it gets funny in a weird way. They said the ECM aka computer (kept calling it a PCM but it is a ECM) was not advancing the timing. Of course I started diagnosing things in my head....was the knock sensor bad or the ESC bad. And finally they said the IAC valve was not adjusting the idle. I figured that mabe the timing problem and the IAC was related.
So I left work early to go get my car as I could figure the rest out as long as I saw the data they had. Got there started checking everything. The computer guy came out, we started talking, he didn't know what I wanted fixed. Aaaaaaaaa maybe the starting issue and the idling issue? Ya think....duh. Anyway he explained the timing issue and grabbed his hand held computer and a timing light. Hooked the computer up started the car up (which ran alot better) and said the temp sensor isn't even reading. I reached down and snapped it back on and said of course not, it wasn't hooked up. Of course he got defensive about it. I told him to calm down and fix my car (but nicer than that). I checked the IAC counts on the computer and they were at 35 which is normal. We moved on to the timing. He said the car was only advancing to 14 degrees at idle. I of course said that is not the correct timing, it should 20+ at idle. I asked if he disconnected the bypass to set the timing and he said he did. He grabbed the timing light and since I was already checking sensors and was dirty, asked if I would disconnect the bypass and pointed down towards my passenger side transmission area. I go .....huh?....that's not were the bypass is. The bypass disconnect is connected to the distributor and is directly behind it? He goes.."Oh, it's not that single brown wire down there?" Uhhhh, no, that's a purple wire that goes to my O2 sensor. Geeze, sometimes you wonder but since it was a custom install I let it go. I disconnected the wire while the car was running and it was rather smooth running but after we put the timing light on it ended up being about 4 degree retarded, which was odd. I broke the bolt lose on the distributor and we adjusted it back to 2 degrees advanced. It's suppose to be 0 but most people turn it to 4 advanced to get better performance from the motor. Tightened everything down and it was idling about 975 and it should be around 700 on a warmed engine. So he said to adjust the throttle stop and handed me a screw driver. Ok, and I started turning it and it wasn't backing down so I kept adjusting it and realized it needed opened so it could come back down. Ended up that it was adjusted to far down so it idled too low but was smooth as a babies butt.
So, in the end, I was able to verify that the IAC is working but it is going to be replaced with a GM IAC as I don't trust the one I put in there and it wasn't operating consistanly, at one point it was at 65 counts at idle. It's getting a new one so it doesn't matter. I'll replace the pressure regulator in the TBI unit and adjust the throttle stop on the TBI back to were it was.
I paid the guys the $79 for hooking it up to the computer and jumped in it and fired it up. That's how I found out the throttle stop was too far away, it didn't want to stay running when I put it in drive and I could barely hear the car running.
She drove great going home, except for dieing when I came to a stop unless i barely cracked the throttle. The car has PLENTY of power and just cruises without sweating. A few things I want to adjust and check on - ps steering seems to hang slightly at a certain point when turning, I feel a slight vibration sometimes but think it's in the wheels, the alignment is out a little so i get some squalling, seat is too close to the dash, the hood is up a little on the driver side front. Other than that it was a good 20 mile ride and the motor felt great and the tranny shifted well. I sure need to fix that speedo, looking down and seeing your going 90 when you know you are not going that fast can be a little freaky. I wouldn't trade a carb for my fuel injection and am glad it is running as smooth as it is, not a miss to be found. Now I can drive her....woooohooo.
Josh
 

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Great News!

Sounds like you have a handle on all the issues Josh. Makes me a little nervous since I haven't gotten to the wiring stage of my build yet. I may be picking your brain later...:nurse: JIM.
 

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Discussion Starter · #3 ·
Pick away Jim, it's pretty interesting making all the old things work with the newer tech.
Josh
 

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Josh.....You've been through a lot with that TBI of yours.....I think your almost an expert on the system now.:):congrats:
 

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Discussion Starter · #5 ·
Lol....if I could only remember all the stuff that I've done to it, Pops. I'm at least excited about driving it now. Hopefully I'll get some wheels soon and finishing the interior and redo the paint and drive it....
Josh
 
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glad to hear about the good/great news josh. :five: you are the expert! :tu ............i think i'll just stick with my carbs after all you have been through. :winking0070:
 

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Discussion Starter · #8 ·
That is great news Josh. I understand how you feel on driving the 57. I like my TBI pretty well myself.
Terry
Yep, smooth and strong plus effecient. My stainless steel duals make it sound nice. I just hung my arm out the window and gave the "nod" at the guys waving and enjoyed it.
Josh
 

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Great to hear it's running nice. Sounds like you need to invest in a scanner tool and save the headach of teaching someone else how to use theirs. :)
 

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Well, it sounds like you needed a little help, but so does the shop you took it to. Biggest thing is you've made progress.

Sounds like an ALDL cable and a scanning/logging program would be a good investment, especially if you have a laptop already. TTS Datamaster is a good one, and I think your TBI system is supported. There's even some freeware out there.

I think the "hitch" in your power steering will go away once you have the timing and IAC right. Reason is, your idle speed is dropping too low when you turn a corner. Low idle speed = low pump flow.
 

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Discussion Starter · #16 ·
Well, it sounds like you needed a little help, but so does the shop you took it to. Biggest thing is you've made progress.

Sounds like an ALDL cable and a scanning/logging program would be a good investment, especially if you have a laptop already. TTS Datamaster is a good one, and I think your TBI system is supported. There's even some freeware out there.

I think the "hitch" in your power steering will go away once you have the timing and IAC right. Reason is, your idle speed is dropping too low when you turn a corner. Low idle speed = low pump flow.
Yep Rick, I basically only took it there to get the data. I started building a cable to hook to my laptop and already have WINALDL program to pull the data but never finished the cable. It is sitting in a kitchen drawer. I couldn't get it to work the first attempt and set it aside for more research. I am thinking I will just buy one, they are only about $50 with the moulded ends.
I would also agree with your ps comment but it catches at any RPM. It is confusing me. The "hitch" seems to be at the exact same place every time. My plan is to swap what is in there now for a 500 series ps box. I did the mods to the 605 box myself and figured I did something wrong but it may just needs worn in a little or I still have air in the system, my brakes work but are not as stout as they should be (hydroboost). Doesn't it take about 500 miles to work out all the air?
Thanks for all the comments, still have a long road to go to finish it though....lol.
Josh
 

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Discussion Starter · #18 ·
Yep Randy, I understand that all too well.

I was working on the customers 57 and was finishing up and heading inside and figured I would start my 57. Fired up and stumbed and died, tired again and it fired right up, adjusted the throttle stop and she runs as smooth as any vehicle I've ever owned. What was really cool was all I had to do was reach through the window and turned the key. Right now I am loving it. Fuel injection...wooohoooo.
Josh
 

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Josh you can have fun and enjoy them without them being totally finished. I hope to finish my interior this winter during my slower time. I have still had a blast this summer driving it and going to shows. Entering it in the "under construction" catagory.
Terry
 

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Discussion Starter · #20 ·
They would make me park out back......lol.
Josh
 
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