baff 10 Posted September 14, 2019 Hey guys, I recently replaced the OEM Bosch distributor with a brand-new one from "JP Group". After swapping it when I start the engine the car revs'up at 2000-2500 RPM and gradually descends to 700-800RPM in about 2-3 minutes then the engine stops. When the car reaches 700-800RPM the idle is very rough. Does anyone have a clue what could be the problem? Quote Share this post Link to post Share on other sites
vw rule 19 Posted September 14, 2019 Hello there, the 16v distributors you can't really fit wrong as they only fit on one way, as a precaution though any distributor you remove from an engine, it's always best to time the engine up to TDC, to rule out any misalignment with engine / ignition timing. The rotor arm should point to number one HT lead on dissy cap, once engine is set to TDC. The 2.0 16v engine should ideally reach 1200rpm to 1500rpm from cold, then once it's off it's cold start program it'll drop down to 800rpm to 850rpm, if you're getting 2000rpm to 2500rpm then the distributor isn't set / timed up correctly, what I mean is the ignition timing of an old distributor compared to a new one is going to be slightly different, sounds light the ignition timing is set too far advanced hence the racing idle speed at 2500rpm ? But then you've mentioned the idle speed does drop down to 700rpm, which really is too slow, and is on the border line to cutting out. Ideally you'll need a timing strobe light to set the ignition timing, or at least to check it's correct. But especially to check the ignition timing when a new distributor has been fitted. You haven't messed around with the idle screw have you on the throttle body, as they are normally set to correct idle in the factory from new, plus normally have yellow or blue paint on them as standard setting up procedure like I say from when new. Have you a strong smell of fuel when it's running rough at 700rpm to 800rpm ?? Or is it popping / banging out of exhaust ?? The idle control valve can cause idle problems, but it won't cause the idle to shoot up to 2500rpm, it normally causes the engine to cut out when hot, or the valve becomes clogged up and sticks causing the idle to drop down slowly or idles at 1200rpm Si Quote Share this post Link to post Share on other sites
vw rule 19 Posted September 14, 2019 (edited) The firing order should be 1,3,4,2 The engine rotates clockwise but the distributor will rotate anticlockwise. Number one cylinder is at the cam belt end, number 4 cylinder is closest to the gearbox or distributor. According to the Bentley Manual for the 9A engine the idle speed should be 800rpm to 1000rpm at normal running temperature = 80° to 87°C Using a ignition timing strobe light, timing should read 6° + or - 1° Correct torque settings for spark plugs is 20Nm (15 ftIb) Engine RPM limit is 5800rpm Once engine is set with correct ignition timing from 5° to 7° (Factory setting is 6° + or - 1° The ECU will then Keep the set timing within range, by using the two knock sensors bolted to front of engine block, and the pick up sensor that's connected to number 4 HT lead. Also states that the timing can NOT be set / adjusted when idle is not normal at 800rpm to 1000rpm, basically the ECU needs a reading from the throttle position switch telling it that it's in the closed position, and is using the idle control valve to idle correctly. Hope this helps Si Edited September 15, 2019 by vw rule Quote Share this post Link to post Share on other sites
vw rule 19 Posted September 15, 2019 I think on the 8v GTI MK2 Golf you can have the distributor out by 180°, but it'll run like a bag of nails or won't run at all. Also you can have the valve timing out by 180° where the cam shaft pulley is out by half a turn, but the engine still runs just but like a bag of nails. I don't think you can have the valve timing out by 180° on the 16 engine as the valves will hit the pistons I think. But you can have the camshaft pulley out of alignment by 1 or 2 teeth, and it'll still run but can affect idle and torque when driving. Si Quote Share this post Link to post Share on other sites
vw rule 19 Posted September 15, 2019 I've just found an old thread from 2013, the guy who started it was having similar issues to what you have, basically it turned out that his valve timing was out by a tooth or two, plus needed the distributor to be set correctly, plus had an issue with his idle control valve. Here's the link below, have a read through it of his symptoms. http://the-corrado.net/showthread.php?80030-9a-issue-with-timing-next-issue Hope this helps Si Quote Share this post Link to post Share on other sites
baff 10 Posted September 17, 2019 WOW!!! I am speechless. I can't thank you enough for the info. Yes, I previously went to a mechanic that modified my ignition timing temporarily. Regarding the idle screw on the throttle body, I thought 9A didn't have one. I also cleaned my throttle body so I will check the screw. Thank you once again for your support! I will comeback with news once I do the ignition timing Quote Share this post Link to post Share on other sites