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I should add that when you feel compression on #1 plug hole, and timing mark is close to zero degrees at harmoic balancer, verfiy that the distributior is pointing to #1 plug wire on the cap.

minor poping is normal, until you can get distrobutior in the ball park by turning it left or right.

Check harness at air cleaner...the wires that feed the injectors...the way the TBI air filer setup is...you can pinch the wires that power the fuel injectors (just something to know).
 
I messed around some more with everything today and still a no go. If I put gas in it with the throttle it will run for a couple of seconds and die. it just doesen't seem to be getting enough gas I'm at a loss. I've checked the timing quite 4 or 5 times now and it is dead on and everytime I look at the pointer its TDC and pointing at #1 cylinder. All the shops around here are closed for the weekend. One thing I did notice is there is some air in the fuel filter would this be anything? No matter what I do I can't get it out. If I run the pump with the line in a bucket fuel comes out just fine in a pretty strong steady stream. It really seems though when the engine starts up it just starves. the injectors don't spray less than when its cranking.
 
have you checked the fuel pressure? Fuel Injection engines are real senstitive to the pressure....not engouh and they will not run. If you have spark and you have fuel...make sure to check fuel pressure. Assume no trouble codes in ECM?

I would not be real concerned about air in the fuel line...it should bleed itself out...you have no fuel leaks ? You have plenty of gas in the tank too?

Verfiy the fuel pressure and that you have the filter in the right orentation relative to fuel flow and you have no mechanical issues with fuel hose or routing.
 
What is a good code reader for these engines? I'm going to go pick one up and see what it tells me.
 
I got a Code reader and the only code it has thrown is a 54 Fuel pump relay. Ill research this a little and see what it might mean.
 
I think you have found part of your problem! Fuel pump relay = what controls the fuel pump. You need a shop manual for the year model truck your engine came from. You may find some info on that online but I would at least go by your local book store and pickup one of teh not so good haynes or chiltons manauls (better than nothing) or go to helmic.com and get the GM manual. I think on the year model vehicle your engine came from.... a code reader is a code reader....not to much info come from the ECM. If you have the $$ you might want to get an automotive scanner tool... I don't know what to advise you on brands as to a reasonablly price one that does a good job, other than to say that the OBDI stuff, you don't need the sophisticed scanners like you do on the newer OBDII and whenever OBDIII comes out.

The bottom line..... you may simply need a new fuel pump relay!
 
The code reader I picked up is pretty cool it tells me the code on the screen that it threw and a Brief description of what it is. Checker let me rent it so I was cool with that It was like 220 or something but they refund you completly when you take it back. I might buy it or soemthing like it though it would be nice to have for my other vehicles. That would be pretty good news if thats all it is. The harness came with a relay so I wouldn't think it would be bad but who knows. If not I can only think it has to be something with the computer. I listened to the message from when my harness was ready today and in it the guy who made it said there was a chance it might not work the same as another computer used in those years so I'm a little concerned he set the harness up for the other computer. I don't understand what the difference is but all it makes me think there might I need the 94-94 year 7427 ecm. I'm trying to find out if there is any differences in the harness setup that would make the 8625 that I have not function with the harness I had made.
 
You need to understand why you are gettting the troublecode for fuel pump relay...and fix that. There are complete trouble code diagnosis charts in the shop manauals. YOu cannot have hard code (trouble codes) set in the ECM and not expect problems.

Trouble codes have to be fixed....sure when you get into custom wiring hanresses and stuff you are going to have some wierd problems. Make sure you don't have a simple cut wire or relay that needs to be replaced. Find out what that code says to check, and work your way through that.

I mean if you have a code that speaks to fuel, ign, spark, or timing....you will have to get that fixed before it's going to run right or run at all. The ECM is the brain of the vehicle...the sensors tell the ECM what's going on... if one of the sensors fail or wires get cut...the ECM cannot operate correctly.

I would simply replace the fuel pump relay, and clear the codes and see what happened then...if I did not have a shop manaual, I'm sure you can get the relay at NAPA or some other store. Then of course if that does not work...you've got to figure out what's causing the ECM to set the fuel pump relay trouble code.
 
Ok I do have the manual so today I went in and checked the the code out. I redid my ground on the fuel pump and now It won't through the code anymore but still will not start. Now it won't throw any codes. I also rechecked my other grounds and everything is ok. Could the IAC or Egr diaphram throw it off or prevent it from starting? When I did the intake gaskets I cleaned up quite a bit of carbon maybe the egr is sticking?
 
I pulled the IAC and it seemed pretty sticky so I cleaned it up no effect then just out of curiosity I pulled the pintle I think its called out a bit and turned over the engine and to my surpise it almsot kept running, so then I turned it over again and worked the throttle a bit and was able to keep it going for quite a while. I'll pick a new IAC up on monday and see what a kind of a difference that makes. It was nice to have some type of response though.
 
IAC does control the idle....if its out of range it should set a code.... But yes if its faulty it's not going to let the truck idle / or most likely run. IF the engine ran without problems previously you should not really have issues with the sensors. I belive there is a formal process for installing the IAC, beyond just plugging it in.
 
Yea when I started reading about the IAC it said be carefull when you clean it, apparently if you get carb cleaner down in there its pretty much shot. I'm worried that when I did the intake gaskets I cleaned it up quite a bit and am afraid I shot it with carb cleaner. I hope I didn't knock some carbon in those air passages either, I'll spray those out and see if it helps on monday.
 
Do you have an inline fuel pressure meter? On a wheeling trip, there was one of the guys that had a TBI setup that was getting some fuel pressure, but his fuel pump was on the way out and it wasn't producing enough pressure to run correctly. He ended up putting an inline fuel pressure gauge and saw it was running low. Have you confirmed that your fuel pump is getting full voltage? Is it producing full pressure?


bk
 
You can test the IAC by jumping the ALDL like you would to read codes, and holding the key in the run position for about thirty seconds. This will cause the IAC to push all the way in and you will here it making a clicking sound. This is how you set the idle speed by getting the plunger of the IAC all the way in, disconnecting it, than setting the mechanical throttle stop, but it also will let you know if the IAC is working. Be carefull when you replace an IAC. You have to work the plunger all the way in by hand, very slowly or you could ruin it by threading it into the housing with the plunger extended.

One more thought. It can make a world of difference disconnecting the battery and letting the rig sit for a while. This starts things back at default settings and the computer will ignore whatever goofy data it has aquired while you farted around trying to make it run. I went through this very thing on my initial fire-up and I was amazed how much it helped.
 
I went and replaced the IAC since if it wasn't bad I probably wrecked it screwing around with it anyway but I still won't run. I've pretty much narrowed it down to some type of fuel delivery problem at this point. If I load the intake up with gas it will sit there and run smooth as butter for a few seconds then just shut off.
 
There is Oil in the truck the oil pressure sensor is brand new. The other oil sensor shouldn't affect it i'm aassuming right? thats just for the guage? Can I bypass the oil pressure sensor somehow?
 
Do you know that the fuel pressure is good at this point in time?
 
No I'm going to pick up an inline gauge tonight I originally assumed it was good since its a new pump and new lines back to the tank. On an intersting note I unhooked the temperature sensor and it popped off first click and ran for about 10 seconds...? I coudln't get it to repeat as the battery was almost dead when this happened. I'm charging it right now to find out. I broke the original sensor and replaced it but why would it run better with it disconnected than connected?
 
I don't know on the temp sensor thing, does not soud like it matters.

So.... you have cleared the ECM codes and no codes set in the ECM as of today?

You can never assume on the fuel pressure issue...it's bitten me in the @$$ too many times.

On another note....not trying to say this is an issue....but I had a MAP sensor go bad on my 5.7 vortec and it made the engine run like crap....but did not set a trouble code.

Yes there is a way to "hot-wire" the oil pressure switch....but Off hand I don't know which wires to jump.

Allthough a little late...do you know if the engine had any trouble codes set before you installed it? And you do have all the sensors connected including the 02 sensor, you don't have any connections not conencted or otherwise missing, to include knock sensor.

Make sure you did not damage the knock sensor when you did the engine swap.
 
After I get a guage on there to see if I have pressure up to the regulator how do you test to see if the regulator is good? Could have this went bad setting for a couple months with no fuel in it?
 
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