Rude55

i have an 87 noticed a fuel leak coming from fuel rail underneath the intake mani. took it apart and the small screw had fallen out of the end of the fuel rail ( looks like a regulator or ?. put screw back in snug, got it all back together and fired it back up and now the darn thing missess after it reaches operating temp. any help please.

black_sunshine

Okay, that little screw has nothing to do with your fuel leak (they move in and out depending of fuel pressure). It means you have a bad Pulsation Damper; the internal diaphragm has ruptured. Those things (PD's) have been the death of more rotaries than anyone cares to talk about. Remove (or replace) that cursed little device and use a banjo-bolt (the one on the primary rail; it's the fuel source nipple) in it's place. DO IT NOW or you'll be running a flaming pile of rubble within a few hours of driving. Summit racing sells individual Banjo-bolt replacments specifically for this purpose, but they're $20+ (and very well made, I might add). Just grab a spare fuel rail, and steal the parts from it (banjo bolt, banjo nipple, and the 2 crush-washers).

As for the rough idle, does it just miss when it's cold (that's normal, BTW) or when it's hot (not-so normal)?

If it does it only when it's cold, don't freak-out. Every car I've ever seen runs like crap until it gets hot.

Now, if it does it when it's hot, then there's another problem at hand. There was a notice in my AllData program issued about a bad thermo-switch. It is located on the driver's side, on the bottom of the radiator. It screws into the radiator, and has 2 wires coming from it. It's just a switch, so it only has 2 states; on and off. Test it when cold (for continuity), and then test it when hot; you should have a circuit (continuity) on one, and an open-circuit on the other. I can't remember which at what temperatures though.

The next thing to replace is the sparkplugs. If the electrodes are ROUND (not cylindrical with a flat top but cone-shaped), replace them. Also note the color of the carbon on them; white is good, black/brown is normal for "easy" driving, and wet is bad.

Plug wires will cause this; don't get the cheap plug wire sets (omnispark) as they're junk. Spend the extra $$ and get a GOOD set.

Other things that can cause this are a bad water temperature sensor (located under the alternator, attached to the water-pump housing), Air Intake Temp sensor (there's one inside the AFM [attached to the air box] and one on the driver's side of the dynamic chamber), and the O2 sensor (exhaust manifold). Make sure you plugged everything in!

There's 3 vacuum hoses on the front (towards the fan) of the Throttle Body. There's 2 on the back of the TB, one right next to the BACV/AWS/AIT, two on the passenger-side next to the firewall, one on the passenger side for the boost sensor, and one on the Lower Intake Manifold, just between the oil/fuel injectors. Make sure every one is connected/capped-off.

The sensors to check for connection are the BACV (driver's side; the motor that has coolant running through it), AWS (same area), AIT (same area), TPS (passenger-side, front of TB), AFM (connected to the air box), and the 2 secondary injectors. Make sure your primary injectors (the ones with the leaky Pulsation Damper) are both plugged-in correctly.

Hope this helps

Rude55

thnx for the advice black sunshine. Ive been busy, sorry it took so long to get back, but I plan on making time to try these adjustments you suggested this weekend.

Rude55

it runs aound 2000-2500 rpm at cold starts then after reaching operating temp thats when it starts acting up feels like its about to jump out of the car, tell ya what i tried before I read your reply, It has a miss, so what i did was unplug the plug wire from the coil pack on the coil pack closest to the front of the car I noticed a change in the way it ran. on the coil pack closest to the firewall, unplugged the wire and no change in the way it ran so I changed that spark plug. fired it back up it and it continues to miss.

Rude55

oh yeah, another thing I noticed is that there is a slight vibration in the car when I increase the rpm its like vvvvvvvvvvroooooommmmm vvvvvvvvvvvvvvvrooommmm it should be steady right??? hahahaa is it making sense or am i making a vrooom out of myself.

black_sunshine

If it's an "out of tune" vibration, check and make certain your fan is centered and is for the correct waterpump (S4 waterpumps have smaller dowels than S5 waterpumps do). It should fit snugly aginst the dowel with no bolts holding it on.

If your car is "searching" for a RPM (hold the gas pedal steady, and the rpm's bounce quite a bit ~750rpm+), it means your Throttle Position Sensor is improperly adjusted or you have a vacuum leak.

Rude55

SOLD THE CAR. NO LONGER MY PROB. GUY BOUGHT IT ANYWAY. I PAID 400 BUCKS FOR THE CAR HAD IT FOR 2WKS AND SOLD IT FOR 800BUCKS 86N/A. THNX FOR ALL THE HELP. BTW IM STARTING TO MISS THE LIL PUCKER