The relay is either a marginal failure and the horn will operate at a lower voltage, you cleaned the socket pins with the swap or disturbed corroded wiring under the fuse block.

Your TPS code can be the sensor, its reference voltage, the wiring or the VCM. I would start with watching the output on a scanner with the engine off with slow sweeps from idle to full throttle to see if the output is smooth. If that's OK check the reference voltage and ground with the sensor hooked up.

Regarding your fuel pressure leak, once you open the plenum, look for cleaned areas indicating a leak from the regulator or tubes. If that looks OK then the question is if its the regulator or a leaking injector(s). Replacing the regulator is a quick trynostic test. After that you can remove the spider poppets, energize everything and look for leaks. That may be destructive testing however because the removal can cause damage from brittle plastic parts. There has been a history of crappy spider replacements after Delco stopped supplying them so a parts cannon replacement can be Russian roullette. If you want to get fancy and there is a rubber section of the return line to the fuel tank then before or after opening everything up you could carefully pinch off the rubber section right after priming cycle being careful not to damage anything to see if that slows down the pressure loss. If so then its probably the regulator. I have not tried this last idea myself on my blazer so I dont know how practical it is given your plumbing layout. In other applications I have used a pair of pliers made for this that wont damage the rubber tubing:

https://cimg2.ibsrv.net/gimg/blazerf...00ed540708.png



George

We were posting at the same time, your good on the relay.

George

I decided to just get into the plenum. Here is what I can see, please disregard all the crap I dropped in there lol. It seems wet and greasy, like maybe fuel was in there at some point. Im not sure how it is supposed to look. Thanks for looking again! If you look just to the top left, you will see the one connector that decided to disintegrate in my hand.
https://cimg6.ibsrv.net/gimg/blazerf...38dacb57fa.png

You are focused, I like it. That is pretty greasy. That cleanish streak up the middle is probably where the current leak is or has been. How many miles are on that spider?


George

Well, I don't know the answer to that. It has 208K on it, I assumed it was never changed. It did have a NAPA fuel pump before I changed it, so maybe it has been replaced. One of the bolts was slightly rounded off on a bracket when I was disassembling, so it could have been gotten into before.

Also on the left side, there are pools in there, like raw fuel maybe, looked pretty nasty I wasn't digging around it just yet.

Ok I decided to just replace the injectors. I don't really like throwing parts at a problem, but since I'm here already I might as well just upgrade it to the better injectors, and it replaces the FPR at the same time.

My next question, is which one do I buy? There doesn't seem to be any Delco/Delphi ones, at least that I can find. I'm not about to put a $90 one from Scamazon in there either.

I found one at NAPA, Echlin brand, based on what I have read it seems to be a decent quality brand. It says its made in the US. I'm not sure if this comes with a bracket or not, I assume not.

Thanks!

I don’t know much about after market choices in the absence of an AC Delco option. That brand is not offered on Rock Auto which is a supplier of quality parts in general. I also don’t see it on Amazon. There, Standard products comes up a lot but the reviews are not very good, a lot of failures. On Amazon the only option that gets good ratings is a TamerX branded rebuild with a one year warranty that is the same CSFI injectors and not the upgrade. I would be tempted by that option. I wish I could offer more on this. As far as the bracket I assume they mean the bracket for the body of the assembly which might be different with a different brand.

George

Advanced auto has the Delphi option which is the conversion,it is expensive and needs to be shipped.


George

Thanks for that I didn't think to check Advance. It seems they don't actually have it though, as when put in cart, says its out of stock. You were not lying about it being expensive, that's a decent amount of cash, more than I paid for this Blazer lol. Ill check around and see what turns up.

I see that Echlin spider made in the USA, 3 year warranty and offered by NAPA where I use to buy a lot of quality parts. Its too bad that it only has one review but that might be a reasonable choice. Also, this does not always mean too much but the price might put it above the trash that gets so many bad reviews most of which cost less than half that.


George