4.3 Vortec cpi pic - need regulator?

[tonyfm]

hmm.... posting rules state i cannot post the pic.

anyway, the passenger side of the plenum looks washed. how do i know it is the regulator?

also does the regulator Help! part # 55162 work on a 1993 4.3 Vortec?

Autozone stated it will not. that they only sell the whole injector for this year. is this so?

thank you, tony

[Jeremy Fitch]

You can post the pic, post it and lets have a look.

[leadalto]

Originally Posted by tonyfm

hmm.... posting rules state i cannot post the pic.

I posted my pic a few weeks ago and the experts thought my regulator looked like it was going and that there was a possible pinhole leak in the "Nut Kit" area. I replaced the whole enchilada (spider and Nut Kit) and that solved my "Rich mixture, black exhaust, gross polluter reading on smog test" problem. I'm still working on my hard starting problem. As the saying goes, a picture is worth 1000 words!

[tonyfm]

leadalto - just got done reading about your situation. read alot about this cpi thing. yeah, pics are the ticket.

not sure what resoution to use though. i could make this bigger but what is the limit?

[leadalto]

Originally Posted by tonyfm

leadalto - just got done reading about your situation. read alot about this cpi thing. yeah, pics are the ticket.

not sure what resoution to use though. i could make this bigger but what is the limit?

I'm afraid I don't know about the limits. I've been setting my pics to 6" wide by 4.5" high (the native Width to Height ratio of my digital camera). I'm using Photoshop 7.0. Sometimes, I adjust the Brightness and Contrast, then I set the dpi (dots per inch) to 72 and save the pic as a .jpg for update to my webspace at Cox cable.

Your picture looks very similar to the one I posted and the washing on the passenger side looks even more pronounced than mine.

The following words and picture are what I posted a few weeks ago:

"I took a picture with another camera looking straight down, Adjusted the image for contrast, color , etc.

Is the small washed area, as pointed, what you suspect is a pinpoint leak in the nut kit? If so, it looks like it's on the return line side.

There is also a big difference in the color of the spider tubes (and nut kit plumbing) from the passenger to drivers side."



Since then, I replaced the spider and Nut Kit which solved the problem I had with Rich mixture, black smoke, lots of carbon stains on the driveway, and qualifying as a gross polluter on my smog test.

[MT-2500]

If you have the plenum off. Prime up the fuel pump and watch for leaks.
Disable coil or dist and bump the key on and you should get a fuel pump prime or jump the fuel pump primmer wire and let the fuel pump run and to get more pressure on it pinch the return line. If it is leaking you should be able to see the leak.
Check around fuel reg and the plastic inlet and return lines. referred to as the nut kit by gm.
Most of the older ones you have to replace the whole fuel spider assembley unless some one makes a replace fuel reg now.
MT

[leadalto]

Originally Posted by MT-2500

If you have the plenum off. Prime up the fuel pump and watch for leaks.

I tried this while troubleshooting and never did see any leaks.

Originally Posted by MT-2500

pinch the return line.

Where, exactly is the pinchable part of the return line that needs to be pinched?

Originally Posted by MT-2500

Most of the older ones you have to replace the whole fuel spider assembley unless some one makes a replace fuel reg now.
MT

Yes, there is one that is available, probably only for certain models. Check the forum FAQ How to's.

For myself, these questions are moot because I've just replaced my spider and nut kit but they were important to me at the time, and still are.

[MT-2500]

Originally Posted by leadalto

I tried this while troubleshooting and never did see any leaks.



Where, exactly is the pinchable part of the return line that needs to be pinched?



Yes, there is one that is available, probably only for certain models. Check the forum FAQ How to's.

For myself, these questions are moot because I've just replaced my spider and nut kit but they were important to me at the time, and still are.

The place you can pinch return line is back of engine to fuel filter.
There is a couple of rubber hoses on the fuel lines . large one pressure and small one return.
Pinch off the small return line at the rubber part or remove it and plug for full fuel pump pressure around 75-85-90 lbs fuel pressure.
It gives you a good idea how good the fuel pump is and helps find them leaks.
Another good indication of a leak is a fast leak down of fuel pressure.
MT

[leadalto]

Originally Posted by MT-2500

The place you can pinch return line is back of engine to fuel filter.

On my 93 S10 Blazer, there are only two places where I found rubber fuel lines. There's about a 6-8" section above the gas tank (not reachable for pinching) and about an 8" section about a foot or two toward the engine from the fuel filter. The fuel filter is about mid point underneath the car, inside of the frame, on the driver's side. These rubber sections are easily accessed for pinching.

[ZL1power69]

from what i've heard from others, the fuel regulator is now availible at places like advanced auto.

[kikwear12]

look throught the phone book for a auto parts warehouse in your arean they sell a regulator for you blazer! it is about $50.00 i know b/c i just got one and since every part is a common part on blazers they usal stock them or can get the regulator for you......

[tonyfm]

replaced regulator. new plugs (old were fouled).

egr moved fine, manifold passage was open.

electronic control module checked out fine from testing at auto zone.

motor has good spark.

idles fine but big time bogging upon acceleration. not drivable.

going to purchase fuel pressure gauge and check with key on. probably will pull the plenum again. i did not key on with the plenum off before.

plese add comments if i missed anything.

[leadalto]

Originally Posted by tonyfm

going to purchase fuel pressure gauge and check with key on. probably will pull the plenum again. i did not key on with the plenum off before.

I did a key on with the plenum off and it didn't prove a thing. No leakage was seen. Regardless of that, replacing the spider and nut kit fixed the problem I had with a RRRRICH mixture. After that, the engine still wouldn't start because I had a feeble fuel pump. In other words, I had two major problems (this may not necessarily be your case).

I thought I'd save a few bucks on a fuel pressure guage by getting a Chinese knock-off at Harbor Freight Tools (a cheap tool retailer on the West Coast and possibly other areas). They had one with a GREAT price $9.99.

Hooking it up to the Shrader valve, I looked forward to measuring the fuel pressure but a major problem occurred when gasoline started filling-up in the guage readout. Well, I thought somebody probably forgot to install an "O" ring or whatever during the assembly process so I exchanged it for another one. Same problem except I was getting tired of exchanging defective junk.

After shopping around, the best deal I found was at an Autozone. They had two choices. One for about $35 which had a short hose and another for about $55 which had a long enough hose to route into the passenger compartment. I bought the $35 version and guess what, no gas filling up the guage readout.

Now that I have a fuel pressure guage, I'm hoping I never have to use it again!

[tonyfm]

yeah was going to get the one from auto zone.

also, my spark was yellow not blue.

if i pull the plenum off and there was a leak in the spider and/or nut, wouldn/t there be fresh wetness or small fuel puddles liek before in order to verify?

[leadalto]

Originally Posted by tonyfm

if i pull the plenum off and there was a leak in the spider and/or nut, wouldn/t there be fresh wetness or small fuel puddles liek before in order to verify?

Possibly! I had some small puddles but it didn't look or smell like gas. It was kind of an oily gunk and not very much of it. I was very reluctant to pull the plenum off but in the final analysis found that it was not very difficult to do and at worst might cost you $11 - $14 for a new gasket to button it up again.

It shouldn't take more than 1/2 to 1 hour to pull the plenum but take care in tagging the bolts because they're all various sizes and some don't come out because they're guide pins. I used a piece of plastic foam and pushed the hardware into it to keep the pieces separated.

Not believing that I had a bad regulator, I even reused the gasket temporarily to do some additional testing (there was no visible damage to the gasket) by coating both sides with vaseline and reinstalling the plenum.

I really never found out whether the failure mode was a bad regulator, leakage, stuck injectors, or whatever; however, after $320 in parts for the spider and nut kit (the nut kit was the most difficult part of the replacement), everything's running great.