I've recently experienced a hard-starting problem, which I think may be due to a leaky fuel injector. The car cranks more than a couple of seconds after it has been parked for an hour or so, but it starts right up when it is cold (like the fuel mixture is rich, e.g. from an injector leak.) I've swapped the IAC, MAP, and MAT sensors from a good running Fiero to eliminate those as the source, and I rebuilt the distributor (new pickup coil and ignition module - with silicon heat goop) and reset the timing, but the problem persists. I tried removing the plug from the engine temperature sensor - the one that signals the cold-start-injector relay - to see if that eliminated the hard starting, but it didn't. Also, the gas mileage has diminished, which adds to my suspicion that the problem is a leaky injector. Now for my question: Where do I hook the fuel pressure gauge to check for leakdown? I don't have a gauge, but I will buy one if you readers concur that the problem is probably the fuel injector(s). I have already contacted a company about cleaning and testing my fuel injectors, but I don't want to go to the trouble of pulling them out if the problem lies elsewhere. Your help will be appreciated.

That was exactly my cause of hard-starting. Leaky injectors. I did find that if I held the accelerator down (so the ECM went into flooded-start mode) it would help the problem to a degree. But I didn't like the idea of raw gasoline dribbling down my cylinder walls washing all that precious lubrication off.

I don't know how efficacious a bleed-down test would be; there is a small calibrated bleed-back built into the fuel line system, I believe.

If you DO pull your injectors for cleaning and calibrating, cruizinperformance (http://www.cruzinperformance.com) has great prices and service.

quote Originally posted by Tom Piantanida: Now for my question: Where do I hook the fuel pressure gauge to check for leakdown? I don't have a gauge, but I will buy one if you readers concur that the problem is probably the fuel injector(s). I have already contacted a company about cleaning and testing my fuel injectors, but I don't want to go to the trouble of pulling them out if the problem lies elsewhere. Your help will be appreciated.

the hook-up for a fuel pressure guage is on the fuel rail. you should see a small knurled cap, and when you undo it, you'll see what looks like a valve for inflating your tires. this is the shrader valve. you screw your guage on there. then, turn your key to the run (not start). go back, and check the guage. turn the key off, go back and check the guage. if its dropping, you've got a leaky injector.

and, as Graudefas mentioned - www.cruzinperformance.com - he does good, quick, inexpensive work - i think its $12 / injector - hard to beat.

Dido what Pyrthian says. The pressure should hold for 10-15 min. or drop veryyyyy slowly.

If it is a v6 you should see about 45psi.

I made my own pressure guage from an old R12 recharge hose that I had and did not have a need for any more.

Cut the hose off, and used a barb fitting, hose clamp and a pressure gauge.

I'm cheap and did not want to pay the $40-50 at the parts store. And had the parts anyway.

DR

Thank you for the suggestions. In fact, the company I contacted about the injectors was CruisinPerformance. I'll hook the gauge up to the (Nick) Shrader Valve. (Nick Shrader is my grandson's name.)