Question about 1986 Chevrolet Corvette

1 Answer

I put a new fuel regulator on my 1986 Corvette and now I have fuel going back into the vacuum lines. Why?

Posted by on

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 10 achievements.


    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Chevrolet Master
  • 426 Answers

Regulator would have to be bad. even if its new.

Posted on Sep 05, 2009

1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

1993 corvette was running great then going about 50 it just quit, cranks but won,t start

check your fuel pressure should be 35 to 42 with key on engine off,and about 5 to 7 more with engine running and vacuum line off the regulator,also check your fuel regulator with vacuum off it should be dry if it is wet with gas it is bad

Apr 30, 2014 | 1993 Chevrolet Corvette

1 Answer

Tpi corvette runs rough intermintely then fine

EGR sticking or mixture control solenoid on carburator if equipped

Apr 20, 2014 | 1986 Chevrolet Corvette

2 Answers

1995 corvette stalls and hesitates at low speed, and when I hit the accelerator hard.

You could check and see if the cattalitic converter is clogged. My friend had the same problem with his 92 Corvett

Apr 19, 2013 | 1995 Chevrolet Corvette

1 Answer

Fuel pressure regulator can it stop your car from starting

fuel lines hook up backwards problem solved...

Dec 31, 2012 | 1990 Chevrolet Corvette

1 Answer

I have changed twice the MAP sensor in Chevy Corvette 1994, but the car continues to run extremely rich

check the vacuum line on the fuel pressure regulator. If there is fuel in it, replace the regulator.

Dec 06, 2010 | 1994 Chevrolet Corvette

1 Answer

89 ford f150 in-line 6 cylinder. i have replaced a few injectors both fuel pumps and filter. idles like a dream. when i hit the gas it studders but doesn't die. need more info ask. any ideas?

This is for a 1989 Ford F150 In-Line 6-Cylinder (4.9L) wrongly posted by the Asker under a 1986 Ford Mustang....

Fuel Injector Pressure Regulator. Look it up on line at any of the reputable auto parts websites to get an idea what it looks like.
There should be a Rubber Vacuum Line coming from this (the Regulator is located on the Fuel Line prior to the Fuel Injectors) to the Intake. Take this Line OFF. If there is gas in that line = The Fuel Injector Pressure Regulator diaphram is broken and the Fuel is being dumped into the Intake and NOT being advanced onto the Fuel Injectors; and the Regulator must be replaced.
Let me know if this helped.

Apr 01, 2010 | 1986 Ford Mustang

1 Answer

Falls on it's face when throttled ,but runs good when rpm's are up.rough idle checked forvacume leaks changed iac valve ,egr,cap and rotor,adjust throttle positioning sensor with butterfly

Slimsoul, a bad fuel pressure regulator would cause a problem similar to this. You may already know this but a fuel pressure regulator kinda works backwards from the way you would think. When your car is at idle it produces the most amount of vacuum which power things like brakes. As your RPM's increase your vacuum drops. When a fuel pressure regulator recieves 0 vacuum it fully opens and allows the most amount fuel to flow through. So, you mash on the gas from idle and the car stumbles from lack of fuel. A common cause of this is because the regulator diaphram has a hole in it, which causes it to open slowly. There is a very simple test for this that, yes, even you can try at home. I'm assuming your corvette is a C4 (84-96). Open the hood, stand on the passengers side, and stare towards the back of the plenum just in front of the distributor. Now look underneath the upper plenum, and attatched to the lower manifold at an approximate 45 deg angle is a round piece that kinda resembles a top hat. This is your regulator. There should be a hard black plastic vacuum line attatched to the regulator. Now for the tricky part, unplug it and crank the car. If the regulator is in fact the problem, this should at least improve if not eliminate your problem. If it does not, my next step would be to check your fuel pressure with a fuel pressure gauge available at Autozone for around $40. A TPI motor needs at least 40 psi to operate properly. Back to the regulator, if it is in fact the problem your going to have to replace the diaphram in the regulator which is somewhat of a pain. You have to pull off the throttle body and upper plenum to get to it. Additionally the FPR is secured with special security torx bits, I believe its a T5. The plenum runner gaskets and throttle body gaskets will need to be replaced if they're original. If you're not somewhat handy I would suggest taking it to a shop to do the job.

Aug 10, 2008 | 1989 Chevrolet Corvette

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

155 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts


Level 3 Expert

75822 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22156 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8201 Answers

Are you a Chevrolet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides