• Got the Contributing Memberships stuff finally worked out and made up a thread as a sort of "How-To" to help people figure out how to participate. So if you need help figuring it out, here's the thread you need to take a look at -> http://www.corvetteflorida.com/forums/showthread.php?t=3581 Thank you, everyone! Rich Z.

427 engine (part 2) - RHS block

Tampa Tuning said:
Im glad she's back home. With that HP, a little stab of the throttle will make you smile and forget most of the problems.

Get some nice miles on the car, and let it break in. Maybe its hungry for fuel at the low RPMs, but it could be turbo lag while building boost, or not enough timing in the low RPM areas.
www.TampaTuning.com
Click to expand...

Yeah, I'm going to take this day by day. Fix one thing at a time and not make any rash decisions...

First thing I did today was to capture the tune file with HPtuners. I kind of felt like I was playing "beat the clock" because it seems that fuel pump would drain the battery in pretty short order. Maybe I should think about some sort of switch inside the car that I could use to turn it off if I just want to run in accessory mode. The pump is pretty loud. You don't notice it when driving because the car itself is loud enough to easily drown it out, but sitting still in accessory mode, it sound like the biggest darn yellow jacket you can imagine being angry at being locked in the trunk. But in any event, I was able to capture the file, so hopefully HPtuners will change my license info for my car so I can use that program without having to buy another license.

I also checked for error codes, but there were NONE. Aaron told me he never found any error codes neither all during the time he was getting that flashing CHECK ENGINE warning. I thought with it going solid on me, it would leave some sort of hint about what it was upset about.

Put the car up on the lift and just looked hard for anything loose. And I found them. Biggest ticket was the passenger side exhaust pipe. It was hitting against the top of the differential. So I just loosened the bolts and moved it over a bit, and that seemed to fix that. Also tied up a lot of braided hose that was just laying loose and knocking around against things. Also noticed that the O2 sensor wires were a bit uncomfortable close to the headers, so I tied them up.

I took a cursory look at the turbo pipe that is visible in the passenger side quarter panel wheel well and it appears to be very wobbly, which would have it knocking against the frame while driving. The STS install normally has everything bolted up pretty solidly, so I'm thinking their might be some part of that pipe not bolted up solidly. I'll take a look at that tomorrow to see what I can find. Tell you what, getting a lift is certainly one of my better ideas.

And I did a lot of cleanup underneath the car. Got pretty ratty looking over the last two years, and the oil leaks here and there certainly didn't help matters much. If nothing else, it was helpful to my frame of mind just spending some "quality time" with the car.

Oh yeah, the gas gauge is working now... :crazy03: Thinking back, I remembered that I didn't hear the telltale ding of the DIC nor the message saying LOW FUEL when I was hooking up the laptop to attach HPtuners for the file download. So no, it's not like there was something loose that got fixed by my tying things up solidly. I did look for anything obvious, like a loose wire that would be causing the problem, but no such luck. And now it wants to slap me a little harder by being an intermittent problem to boot. Well, hopefully it will work often enough for me to be able to keep tabs of how much gasoline I have before I run dry.
 
Rich Z said:
Yeah, I'm going to take this day by day. Fix one thing at a time and not make any rash decisions...

First thing I did today was to capture the tune file with HPtuners. I kind of felt like I was playing "beat the clock" because it seems that fuel pump would drain the battery in pretty short order. Maybe I should think about some sort of switch inside the car that I could use to turn it off if I just want to run in accessory mode. The pump is pretty loud. You don't notice it when driving because the car itself is loud enough to easily drown it out, but sitting still in accessory mode, it sound like the biggest darn yellow jacket you can imagine being angry at being locked in the trunk. But in any event, I was able to capture the file, so hopefully HPtuners will change my license info for my car so I can use that program without having to buy another license.

I also checked for error codes, but there were NONE. Aaron told me he never found any error codes neither all during the time he was getting that flashing CHECK ENGINE warning. I thought with it going solid on me, it would leave some sort of hint about what it was upset about.

Put the car up on the lift and just looked hard for anything loose. And I found them. Biggest ticket was the passenger side exhaust pipe. It was hitting against the top of the differential. So I just loosened the bolts and moved it over a bit, and that seemed to fix that. Also tied up a lot of braided hose that was just laying loose and knocking around against things. Also noticed that the O2 sensor wires were a bit uncomfortable close to the headers, so I tied them up.

I took a cursory look at the turbo pipe that is visible in the passenger side quarter panel wheel well and it appears to be very wobbly, which would have it knocking against the frame while driving. The STS install normally has everything bolted up pretty solidly, so I'm thinking their might be some part of that pipe not bolted up solidly. I'll take a look at that tomorrow to see what I can find. Tell you what, getting a lift is certainly one of my better ideas.

And I did a lot of cleanup underneath the car. Got pretty ratty looking over the last two years, and the oil leaks here and there certainly didn't help matters much. If nothing else, it was helpful to my frame of mind just spending some "quality time" with the car.

Oh yeah, the gas gauge is working now... :crazy03: Thinking back, I remembered that I didn't hear the telltale ding of the DIC nor the message saying LOW FUEL when I was hooking up the laptop to attach HPtuners for the file download. So no, it's not like there was something loose that got fixed by my tying things up solidly. I did look for anything obvious, like a loose wire that would be causing the problem, but no such luck. And now it wants to slap me a little harder by being an intermittent problem to boot. Well, hopefully it will work often enough for me to be able to keep tabs of how much gasoline I have before I run dry.
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My guess is they've by-passed the fuel pump relay or have the pump wired incorrectly!:thumbsup:
(I'd find out what they've done and change it back to factory for SAFETY reasons!):thumbsup:
Below is copied from the GM Factory Service Program as to the way it's supposed to work!:thumbsup:

Fuel Pump Electrical Circuit Diagnosis
Circuit Description
When you turn ON the ignition switch, the control module enables the fuel pump relay which powers the fuel pump ON. The fuel pump remains ON as long as the engine is cranking or running and the control module receives ignition reference pulses. If there are no ignition reference pulses, the control module shuts the fuel pump OFF within 2 seconds after the ignition was switched to the ON position or if the engine stops.


As far as your gauge itself,I'd guess that there are deposits on the cards in the tank from setting around for a couple years with Nasty Fuel!:thumbsup:

After you get the pump sorted out,Put in a 20 oz bottle of Techron Concentrate Plus and top off the tank. Your gauge cards will probly clean up and start working correctly!:thumbsup:

PS I'm going to Missouri for the Holidays to see my Grand Daughters and whats left of my Family,but after that I'll be in South Florida for a few months!
If you have a Cot and the Grub,I'd be glad to come by for a few days and we could sort some of it out!~!!!:thumbsup:
I always have my Scanner,Digital Probe,Laptop with GM Service Programs and a few hand tools with me!:thumbsup:

:D
 
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gmjunkie said:
My guess is they've by-passed the fuel pump relay or have the pump wired incorrectly!:thumbsup:
(I'd find out what they've done and change it back to factory for SAFETY reasons!):thumbsup:
Below is copied from the GM Factory Service Program as to the way it's supposed to work!:thumbsup:

Fuel Pump Electrical Circuit Diagnosis
Circuit Description
When you turn ON the ignition switch, the control module enables the fuel pump relay which powers the fuel pump ON. The fuel pump remains ON as long as the engine is cranking or running and the control module receives ignition reference pulses. If there are no ignition reference pulses, the control module shuts the fuel pump OFF within 2 seconds after the ignition was switched to the ON position or if the engine stops.


As far as your gauge itself,I'd guess that there are deposits on the cards in the tank from setting around for a couple years with Nasty Fuel!:thumbsup:

After you get the pump sorted out,Put in a 20 oz bottle of Techron Concentrate Plus and top off the tank. Your gauge cards will probly clean up and start working correctly!:thumbsup:

PS I'm going to Missouri for the Holidays to see my Grand Daughters and whats left of my Family,but after that I'll be in South Florida for a few months!
If you have a Cot and the Grub,I'd be glad to come by for a few days and we could sort some of it out!~!!!:thumbsup:
I always have my Scanner,Digital Probe,Laptop with GM Service Programs and a few hand tools with me!:thumbsup:

:D
Click to expand...

Well, the entire fuel system was replaced with an aftermarket external pump. I believe it's an Aeromotive fuel pump if I remember the brand name correctly. But obviously when Harwood did the rewiring, he didn't use the circuitry for the original pump, as it remains running for as long as the key is in accessory mode. He just ran the power wire for the pump directly to the fuse box. I guess this would be quite dangerous if the car is in an accident and power is still being applied to the fuel pump. If I decide to keep the car, I might just have all that crap taken out as I don't think it is really necessary for my application. Aaron commented that the Aeromotive wasn't really necessary for the fuel demands of the engine.

Thanks for the offer of help. Let's see what the situation is at that time.

Have fun on your trip to Missouri! :thumbsup:
 
Rich Z said:
Well, the entire fuel system was replaced with an aftermarket external pump. I believe it's an Aeromotive fuel pump if I remember the brand name correctly. But obviously when Harwood did the rewiring, he didn't use the circuitry for the original pump, as it remains running for as long as the key is in accessory mode.
Click to expand...

What we did on my car was we kept the stock fuel pump, and then added a big external that is on an RPM-activated switch that kicks in at 3000 RPM. You might try something similar, keep what you have and put a stocker back in. I think there's a one-way valve in there to keep the big pump from backflowing into the little pump.
 
Gannet said:
What we did on my car was we kept the stock fuel pump, and then added a big external that is on an RPM-activated switch that kicks in at 3000 RPM. You might try something similar, keep what you have and put a stocker back in. I think there's a one-way valve in there to keep the big pump from backflowing into the little pump.
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That sounds like a good idea. I'm not real crazy about that Aeromotive unit whining away.

I took a look at that turbo pipe in the passenger side quarter panel wheel well, and I can't see where it may be loose at. It's not loose at the connector closest to the turbos in the rear, so it must be up front somewhere. I'm thinking it may be a hose clamp loose, which would also mean that boost would be leaking. It appears to me that the pipe is just pushed back too far, and that is pushing the plastic wheel well out from the front of the wheel well.

One of the hood strut shocks was missing, so I found that in the trunk. Somehow the strut got stripped out of the bottom piece, so I have that set up in JB weld right now.

While I had the hood open, I snapped a few pics of the engine....
 

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Oh yeah, here's a pic of the car sitting in the lift bay in my garage...
 

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IIRC it is an Aeromotive A-1000 or the newest (well back then) equivalent.

If nothing else you can use the factory fuel pump wiring to control a relay that turns the Aeromotive on and off. that way if the inertia switch is activated in an accident then the pump will cut off.
 
85vette said:
That engine looks massive! I'd love to hear that thing run!
Click to expand...

Maybe tomorrow I'll start it up and take some video of idle and some light revving of the engine. It does sound pretty good.

Plus Connie said she saw some smoke from the tail pipes when I left Aaron's place on Friday. I want to see if any smoke is visible in that rpm range where there seems to be misfires or something odd going on.
 
Benjamin said:
IIRC it is an Aeromotive A-1000 or the newest (well back then) equivalent.

If nothing else you can use the factory fuel pump wiring to control a relay that turns the Aeromotive on and off. that way if the inertia switch is activated in an accident then the pump will cut off.
Click to expand...

I wonder why neither Harwood nor Aaron chose to go that route? Seems like that would have been the reasonable way to go about it..... :shrug01:
 
Well, I think this explains why misfires (if they are taking place) are not showing up in the error code log. Got someone looking into the tune file and he told me about this one...

DTC_01.jpg
 
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To explain what the above image means, "SES" means the Service Engine Soon" indicator on the DTC display. The various codes in the Error Mode column mean:
  • 0 - MIL on First Error: Illuminates MIL the first time DTC sets.
  • 1 - MIL on Second Error: Illuminates MIL if fault is active for 2 consecutive driving cycles.
  • 2 - No MIL Light: Does not illuminate MIL, but will illuminate SERVICE light.
  • 3 - No Error Reported: Does not illuminate MIL or SERVICE light.

"MIL", by the way, means Malfunction Indicator Lamp.

So I guess I am puzzled. Why was this completely turned off if misfires were suspected? Hopefully I can get a new license to compensate for the replaced PCM from HPTuners so I can turn this indicator back on to see what I get.
 
Rich Z said:
I wonder why neither Harwood nor Aaron chose to go that route? Seems like that would have been the reasonable way to go about it..... :shrug01:
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I think Harwood was in "Racecar" mode and wired it as it would normally be (minus any kind of safety switches that any normal sanctioning body would require). Aaron was in the "if it ain't broke don't fix it" mode.... and can you really blame him, BUT if he did go this far into the build I would think he might should have wired it through the inertia switch at least, but I am no mechanic by trade so what do I know....
 
and one more thing, can you please let me know how the coating is holding up on the turbo's? IF i need to touch them up from any handling / installation damage I will. I would also like some pictures installed for my website if I can get some.
 
Benjamin said:
and one more thing, can you please let me know how the coating is holding up on the turbo's? IF i need to touch them up from any handling / installation damage I will. I would also like some pictures installed for my website if I can get some.
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Well, since the time you coated the turbos, they were sent off and rebuilt as well has having larger housings put on them. So they came back just cast iron, and of course are all rusted up now. I'll probably just clean them up with a rust remover and paint them with high temp header paint one of these days.

Thanks for asking about them...
 
I talked to Aaron on the phone today and asked him about the misfires being blocked out of the tune. He said they needed to do that because of the camshaft. The overlap causes issues that will trigger false misfire readings.

He's going to order some longer coupling hoses for the turbo pipes so he can fix that one extending into the quarter panel wheel well. I commented about the apparently overly rich AFR in low RPM levels, so he said he would ask Jim Smith about this when he comes up next week.
 
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