poor running 454 TBI

[VileZambonie]

I doubt it's your timing chain jumped.

Time it correctly. Did you put the EST in bypass mode? Tan wire with the black tracer needs to be disconnected. If it's a 454 it's near the distributor taped to the harness. With the EST in bypass set the timing to 4° BTDC

Once you do this and lock the distributor down, shut it off and reconnect the the bypass wire. Then clear the DTC you set by disconnecting the battery.

Once you do this then report on how it behaves with any symptoms that come back.

[Cowboy_Customs]

Hmmm, tan wire with a black tracer...... I'll go out n have a looksie right now, I gotta go on a road trip for a day or 2. (yeppy, back to VT, canada border again.) Its a PITA for me to get back in there to look around, between the A/C and my belly..... 
Thanks for the tip. I will report back soon.

[Cowboy_Customs]

I can not find any wire any where thats on or in that loom. The only wire I can find thats taped to anything near there is the Tach lead off the coil, and pair of wires (one tan or white and one black)  that come out of the loom and bolt to the back of the passenger side head which serve as a ground? It may be there but I just can not get to it, there are so many wires and vacuum lines on this thing. Should it really be this difficult to locate this darn wire?


Every darn wire on this thing thats supposed to be white or tan are all tan with black on em lol


Is there anywhere that have a picture of it or am i going to be stuck with pulling the distributor again just to locate it?

[VileZambonie]

It will be taped to the outside of the conduit with a black connector.

Look toward the bulkhead connector to the left of and below the wiper motor

[Cowboy_Customs]

OHHHHH! Its down there! I have been looking by the distributor!!!  THANK YOU!

[Cowboy_Customs]

OK, timing checked and set. No change. The computer is adjusting the timing for sure when its not in bypass. Were pointing the finger at the throttle body now, SO, im going to go ahead and get a TBI rebuild kit from Advance or NAPA tomorrow and see what happens. Also getting the pressure check fitting for the throttle body on the way as well.

Oh, what is the stock PSI rating SUPPOSED to be pre throttle body? I think I remember seeing it somewhere being 15 PSI?

[Captkaos]

12-18 before the regulator.  Make sure you get the WHOLE kit for the TBI.  Gaskets and the regulator pieces, they have a kit that has it all....

[VileZambonie]

Key on engine off fuel pressure should be 9-13 psi. Did you check the engine coolant temp sensor?

Resistance  185 ohms at 210 deg F
  450 ohms at 160 deg F
  1800 ohms at 100 deg F
  3400 ohms at 70 deg F
  7500 ohms at 40 deg F
  13500 ohms at 20 deg F
  25000 ohms at 0 deg F
  100700 ohms at -40 deg F

When the coolant temperature is low, the sensor produces a high resistance. When the coolant temperature is high, the sensor produces a low resistance

[Cowboy_Customs]

Im going out to tinker with it some more today. No I havent checked that yet, i will today and report back, n finally get that video of what its doing like i said id do.

I have rebuilt the fuel pressure regulator, just for grins, I figured it probably hasent ever been done. I did take the whole Tbody off and clean the heck out of it, it wasent really bad at all. Put new base gasket on, regulator and associated gaskets. Im going to put on the new injector pigtails today as well. I may run a compression test as well, I usually do that the first time i pull plugs but havent yet.

I have been running "Seafoam" fuel treatment to give the system a good cleaning, plus ran some straight through the Tbody like it said to do. To date, with the tinkering ive done its ate 6-7 gallons of 93 just in my driveway! ( I only run decent fuel, no crap gas in my gas burners )

[VileZambonie]

87 vs 93 isn't crap gas. You are actually going to get worse mileage and performance out of 93 than out of 87 in your truck. 93 is less combustible at lower temperatures and is designed for higher compression ratio engines. If you don't have the benefits of a higher compression ratio you will see no benefits from higher octane fuel. Odds are you are not creating as much cylinder pressure as you would with 87 and are not completely burning all of the 93 in combustion plus you are paying more per gallon of gasoline. Unfortunately gas companies lead you to believe otherwise by labeling fuel pumps, "regular - mid grade - and premium" which is false advertisement in a way.

[Captkaos]

Ditto on what Vile said on the octane.  Think of it this way.  If you put your gasoline on a scale from highly flamable to water, 93 would be on the water end and 87 would be the highly flamable end.  Not only will it get more mileage, the engine will make more power, this has been proven several times.

[Cowboy_Customs]

ARGH! so I got my fuel pressure gauge fitting deal for the truck, tried installing. No go. I bought one from xtremefi on fleabay for the back of the throttle body, I cant mount the giggered thing!! I have to modify and re flair my supply line to clear the stupid distributor and coil. Will it mount back at the fuel filter?? I would try it, but I have welding class in an hour, and after that im going out of town again till late tomorrow night. I did get a video of what the truck is doing BTW and will get that posted thursday.

[VileZambonie]

Just tee in at the filter. You shouldn't need any special gadget other than your TBI fuel pressure gauge. Autozone sells them for like $15- $20 bucks

[Captkaos]

What does it look like?  The one from autozone is what I have.  it just tees into the line at the filter.

[Cowboy_Customs]

 BINGO!

Fuel pressure! Fortunatly for me I didnt go to VT last night 
So today I put my lil valve in at the filter. I discovered 2 maybe 3 PSI. Then discovered some tard has cobble jobbed my fuel system. It goes like this, from the driver tank (passenger tank in the bed right now) about 6 inches before the switcher valve someone put in a stupid lil clear plastic filter, and completly bypassed the switcher, except for the electronic portion of it, then onto the factory system with the stock filter. AND NEVER changed the additional filter after it was put in. 

I removed the plastic POS and ran the lines BACK into the switcher, so now its factory again. The switcher works by the way (moron!) and now have 5PSI pre filter. With that 2-3 psi jump the truck WANTS to run again!!!!

So, now when I get paid I will be putting in a new fuel pump.

here is a link to the lil valve I bought BTW (if u by this, it will NOT work on the back of the t-body w/o modification, it will screw directly into the stock filter)
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEBTOX:IT&item=260187275488&_trksid=p3984.cTODAY.m238.lVI

OH quick question, Bosch has an upgraded "turbine" pump, is it worth the extra couple bucks, and 26PSI? (that might come in handy later down the road) plus, do I REALLY NEED a strainer??