gtboiii11

Just did a new fuel pump, and new fuel sending unit and tank on my 95 blazer. Now when i give it guess when driving the engine doesnt fele liek it is receiving gas and sometimes the truck will just read check guages and shuts right off. I think this needs a fuel pressure regulator now, engine light is on and comes up a knock censor and o2 censor. The knock sensor reading is due to low fuel pressure and i need to know whats causing it, any good suggestions>

drdd

have you searched "cpi" and "nutkit" on this forum?

wolfox

Try the cheap fix first - a $7 fuel filter. Tossing a fuel regulator at what typically may be a sub-$20 problem is well...like giving me that $20. I am taking donations for my intake gasket repair, btw...

gtboiii11

did a new fuel filter abotu a motnh ago, got soem added power back at the time but now i think the problem is something different

wolfox

Again, for a sense of closure, and as stated in the other thread where you are wrestling your transmission: work through a checklist of Tune-up parts. Of particular note, standard replacement wires (resistor type) and OEM AC-Delco plugs gapped to .045 work best in these engines. AC-Delco Platinums work good too, but fancier Bosch style plugs create missfires as do "High Performance" wires. (Avoid Bosch Platinum +2/3/4's like the plague!) However, using a set of Bosch Super copper resistor plugs in the size and heat range for this engine will prove helpful when replacing that #3 plug. (The one covered by your steering wheel shaft) They are a full 1/4" shorter than OEM and allow easier access of tools and a wobble extension through the wheel wells. Sticking to OEM ignition replacement parts for your cap and rotor are proven best too. I chucked a brand new cap and rotor for a GM cap and rotor when swapping for a set of "High Performance" brass parts proved almost lethal. NAPA Gold air filters work damn fine, and I can vouch for Fram fuel filters, but pass on their oil filters. Again, use the search feature to look up the parts manifest for a complete tune-up on the truck, I am certain I am missing a few things.

BlazerLT

You will have to remove the round IMTV valve on top of the engine under the vortec plate and look down into the plenum and check for washing and leaking fuel.

Also smell your oil, I bet you it will be high and smell of gas.

Search for CPI injector and nut kit.

Also, the fuel pressure regulator will often only patch the job.

Seeing you will have the plenum off to replace it, you might as well replace the whole injector AND nut kit and be done with it.

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1995 Factory Blazer Service Manual for sale, PM if interested.

gtboiii11

no gas smell in the oil and oil level is normal, i couldnt see into the plenum very well so i am just taking it off, i seem to have all the bolts out but it is not coming off

BlazerLT

You will have to pry up on intake section to have it pop off, just remember, you need to replace the plenum gasket if you are removing it.

You can't just install it back together with the old one.

__________________
1995 Factory Blazer Service Manual for sale, PM if interested.

gtboiii11

so i ended up getting the pressure regulator for the 95 and the 96 just to be safe and both are very different but neither looks like the right one, where exactly is the regulator located in the cpi unit because the parts i have dont look like it, is there possibly a diagram somewhere?

gtboiii11

nevermind neither part is right so i am just going to do a tune up and put it back together, i found no sign of gas in the intake manifold, it just seems the cpi egr valve and the entire inside are caked with carbon so i am just going to clean them , give the truck a tuneup and see how things go, i didnt even smell gas in the oil.