I posted about this over a year ago but nothing really showed up defective at that time. Few years ago car always would start up right up any time. Now it usually starts after cranking 3-5 seconds. Holding my foot to the floor helped to lean it, but was not a cure. I basically attributed it to leaker injectors and would just live with it till I changed them. Other than that the engine runs great.

So this past weekend I got a wild hair and decided to look at the fuel pressure again. In 15 minutes it drops from 40 to 20 lbs, and between 30 and 45 minutes it is 0 lbs. Took the vacuum hose off the FPR and did not really see much, maybe one drop. I attached a clear tube off the FRP and pressurized the system. I watched in amazement the tube fill up. At least ½+ oz of gas filled the hose.

Due to gravity, it was running down right in the manifold causing it to be rich every time I went to started it. To say nothing about the mileage and waste of fuel it uses. So now I am searching for a better price on a FPR other than the GM dealer at $157.

Hopefully this will make the difference and fix the hard starting.

 

Where did you attach the clear hose? Vacuum?

 

The vacuum hose from the engine was removed from the FPR. The clear piece of hose was attached to the FPR and the other end let free but at an up angle. Then key on, pump runs 2 seconds, key off. System is pressurized.

Then just watch to see if any fuel comes out of the FPR into the clear hose. Nothing should ever happen, gas should never back up out of the FPR. If it does, FPR is bad.

 

I agree. Just wasn't sure which tube you were talking about.

 

Just installed the FPR. On initial turn on it is 46 and falls to 44 lbs when pump shuts down. In 15 minutes still reading 38 and an hour later seems to stabilize at 34. Much better than before.

No fuel coming out of vacuum fitting as it should be so all looks good. Have started it a few times already and starts right up, no cranking like before. But I will see what the actual affect is when I start using the car on Monday.

The only thing that bugged me was the vacuum fitting is slightly smaller than the original GM FPR. So I put a tie wrap on the hose for a tighter fit. This was a Sorensen unit which I was able to get ASAP and did not want to wait for the Delphi unit.

 

I also have a strange intermittent cold start issue. Sometimes have to crank 10 times before she fires up. Lots of clouds of smoke after fire up too that dissipates pretty quickly. Does it sound similar or could it be what someone suggested to me "leaky valve stem seals" or problem with cold start injector?

 

Frankly you description is not the symptoms I had. It started every time but just took a few extra seconds till the excess fuel was expelled and the mixture was good enough for combustion. When the engine started there was no smoke but only the smell of a rich mixture from the exhaust. By me holding my foot to the floor till it kicked reduces the injector pulse thus it does not keep adding to the already rich mixture.

My 2 cents IMHO for your year.
First determine if the smoke is oil or fuel. Are you using oil excessively. Pull a couple plugs and look at them, see if they look oil socked.

But in all the posts I have see injectors are a real source of problems in those type vintage years. I would start out measuring the resistance of each injector. I think the 87 have 12 ohm injectors and all should measure within 0.5 ohms. I would also perform this test with the engine hot and see if results change drastically. Now the resistance of the coil in the injector has nothing to do with the actual valve sealing anyway. They can still leak.

I would definitely perform a fuel pressure check to see what the leek down is. If it is leak down is bad and the FPR is OK, then it might be necessary to pull the injector assembly and pressurize the system and see if any injectors are leaking under pressure. Do the same with the cold start injector.

We really need an “87” type guy in here with his specific knowledge of that car (like Agent86). Excuse me if I have an error in some way in resistance of the injectors but the concept is the same. Any corrections welcomed.

 

Could not wait to report on the outcome. Its like a different car now, or at least the way I remember from back in time. Starts right up, day, night, hot or cold. No more smell or roughness and pops right off.

Hope some others have the success I have had in this one.

 

Simplicity at its finest!!!

 

me too