HI I HAVE A 86 GT 2.8 , ALL STOCK, IT RECENTLY STARTED A POPPING SOUND FROM EXH. PIPES. I SEARCH FOR ANY EXH LEAKS AND NONE FOUND, THEN I STARTED CHECKING FOR POSSIBLE IGNITION PROBLEMS, I REPLACED PICK-UP COIL, IGN. MODULE, SPARK WIRES, CAP, ROTOR, PLUGS, NO HELP, CHECK RESISTANCE ON COIL CHECKED GOOD, (REFERENCE FROM FACTORY SERVICE MANUAL) HARMONIC BALANCER IS NEW, FUEL PRESS WAS 45 PSI AND STEADY PRIOR TO START UP AND STAYS AT 38 PSI WHILE RUNNING, CYLINDER COMPRESSION TEST WAS GOOD, HIGHEST WAS 145 PSI, LOWEST 130 PSI . ALL HOLDING. THE PROBLEM I AM HAVING RIGHT NOW IS THE TIMING CHECK. I SET THE #1 CYL TO TDC WITH WIDE NOTCH ON BALANCER SET TO "O" ON TIMING MARKS (VERIFIED PISTON IN CORRECT POSTION BY STRAW METHOD, AND FINGER OVER SP HOLE.) I SET ROTOR BETWEEN #1 AND # 6 DIST. TERM POST (NOTE: # 1 SP POST IS BEFORE THE TRUNK SIDE HOLD DOWN POST) I SHORT OUT TERMINALS ON ADLS,SES FLASHES 12, NO CODES, AFTER I STARTED ENG,SES FLASHES QUICKLY, I CAN HEAR THE IAC MOTOR IN TIME WITH SES LIGHT???? LOOK AT THE BALANCER TO TIME IT AND THE MARKS DONT ALIGN. I ROTATE DIST. CW AND CCW, STALLING ENGINE AND NO MARK ON BALANCER NEAR TIMING MARKS I ADJUSTED TIMING, BASE ON RPM ON TACH (900 RPMS) IT RUNS OK AT IDLE AND HIGHER SPEEDS. I STILL HAVE SOME POPPING SOUND ON DEACCELERATION, AND WHEN I STEP ON THE ACCELERATOR. ANY IDEALS, THANKS FOR ANY HELP, PS THE MAP, CTS, EGR VALVE, TPS, HARD PLASTIC VACCUM LINES WERE REPLACED SORRY I TYPE LIKE THIS ALL THE TIME EVEN AT WORK . THANKS
Jet Blue doesn't have 319's do they? I'm an A320 Captain for USA 3000 Airlines.
Instead of putting your timing light pickup on #1 wire, use the coil lead. Your timing light will flash every time the coil fires. The harmonic balancer has marks every 120* so a mark will be under the light each time the coil fires. This makes "averaging" the #1 and #4 cylinders easy.
Also, the outer ring of the harmonic balancer has been known to slip. The marks will never line up in that case. You will need to replace the balancer if that is the case.
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10:23 PM
Oct 29th, 2009
Indiana_resto_guy Member
Posts: 7158 From: Shelbyville, IN USA Registered: Jul 2000
Sounds like you didn't index the new balancer, depending on where you got it. If your trying to set inital timing and the marks are correct, set the timing marks on the crankshaft at 10* BTDC, rotate the distributor rotor to strike # 1 plug wire post on the cap and install and tighten. Short the terminals on the ALDL, have the inductive timing light at the ready and start the car. Check the marks at this setting and adjust as necessary. If you still hear a pop from the exhaust you may have carbon build up in some cylinders causing detonation on the exhaust stroke. Run some quality fuel system cleaner through it that will clean the cylinders of carbon build up. If that doesn't work it is possible the valve lash is too tight by a smidge or you have some bad exhaust valve seats.
[This message has been edited by Indiana_resto_guy (edited 10-29-2009).]
the balancer is new and i had the painted wide groove set at zero and piston at tdc (verified by thumb over sp hole) i set the rotor to between #1 and #6 dist. term, when i set the timing light up and inducter clamp on #1 sp wire . the timing marks at no where near, the car idles at 900 but i hear the popping sound on decelaration and during initial acceleration now car stalls out at idle with ac on while waiting at light i will try the high octane gas and gas cleaner, would a egr valve have any affect? it was replaced also prior to this thanks for your help and keep the input coming
your right jetblue does not have 319 just 320. i retired from US AIRWAYS working on Airbus
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06:42 PM
Indiana_resto_guy Member
Posts: 7158 From: Shelbyville, IN USA Registered: Jul 2000
the balancer is new and i had the painted wide groove set at zero and piston at tdc (verified by thumb over sp hole) i set the rotor to between #1 and #6 dist. term, when i set the timing light up and inducter clamp on #1 sp wire . the timing marks at no where near, the car idles at 900 but i hear the popping sound on decelaration and during initial acceleration now car stalls out at idle with ac on while waiting at light i will try the high octane gas and gas cleaner, would a egr valve have any affect? it was replaced also prior to this thanks for your help and keep the input coming
your right jetblue does not have 319 just 320. i retired from US AIRWAYS working on Airbus
When you verified your timing with the light, was the A & B terminal shorted at the ALDL? If not the timing mark will be off about 30* or better. Where did you get the balancer out of curiousity?
the balancer is new and i had the painted wide groove set at zero and piston at tdc (verified by thumb over sp hole) i set the rotor to between #1 and #6 dist. term, when i set the timing light up and inducter clamp on #1 sp wire . the timing marks at no where near, the car idles at 900 but i hear the popping sound on decelaration and during initial acceleration now car stalls out at idle with ac on while waiting at light i will try the high octane gas and gas cleaner, would a egr valve have any affect? it was replaced also prior to this thanks for your help and keep the input coming
your right jetblue does not have 319 just 320. i retired from US AIRWAYS working on Airbus
Wow, more pilots on the forum than Fiero owners.
For what it's worth, I would be tempted to double check my indexing on the harmonic ballancer, you know, get that as exact as possible. I've set my rotor directly at the # 1 post when installing the distributor but that's me. Ground the ADL then start the car, I usually set the timing as the engine is warm. Note, in diagnostic mode (adl grounded) the check engine light will be flashing, that's how i know I've got it grounded,
After timing is set, I usually will disconnect the negative battery cable to clear the ECM, that'll clear out any "learned" behavior, then reconnect it and take the car for a drive over 35 mph. Don't waste money on premimum, just use the regular with injector cleaner. (unless you've got avgas100, just kidding)
I would look to clean the IAC with throttle body cleaner, that might help the stalling at lights. Also, check your battery, battery connections and grounds as the AC will draw alot of electrical power and that can sometimes stall the engine.
Good luck.
Little story.... Many, many years ago, I used avgas 100, the green stuff, in my little 96 pound hydroplane boat, only like a 16 Hp outboard, jacked the timing to handle it, darn thing ran like a bat out of hell, over 55 mph if I tucked myself tightly into the cockpit, could never get out of the airport without drawing attention to the hydroplane. Fun stuff.
edit speling.
[This message has been edited by jetman (edited 11-02-2009).]
i cleaned out the IAC PORT, and there was no change, i did change the ECM coolant temp switch, even though there was no fault code . my stalling was gone. i removed my 9 month old egr valve and found the seat was sitting in a angle causing the valve to stick open. the popping sound was reduce but still there.. i decided to start over and set timing with balancer set at 10 deg and the piston at TDC, set the rotor pointing to the nbr # 1 distributor terminal and the # 1 sp wires set to the terminal after the holdown screw like in the Haydes manual. shorted out ADLS TERMINAL. still no alignment with balancer and timing marks but after a few turns on the distrubitor i got most of the poping sound to go away. it idles at about 900 rpm. will keep wking on this? thanks jetblue
When you are trying to time it with the ALDL jumpered what is the idle speed? Mine would idle way low like 500 or 600 rpm. From your description it sounds like you have it nailed with finding TDC on #1. I just don't understand why your timing marks are not close unless the car is not in diagnostic mode.
it idles at 850-900 rpms after warm up. it drove since and quiet but i did still hear some popping on sudden decceleration. acceralation is good, no noise. but i can figure why the marks dont align. everything is set right, piston on near tdc, balancing mark at 10 deg btdc, rotor at # 1 distrib. term (base on hayes manual ref.) and adls shorten out. i do get the SES light flashing 12. with eng off and no fault codes. and a flashing SES light with eng running and a increase in idle speed. but no alignment. if i use the adls connector with the computer program can i set timing with that? where can i get adls computer connecter and program.? thanks jet