So engine starts running rough at idle, hard to start (crank for 10 secs or more), occasional stall while driving, rough at cruising, running hotter than usual. I suspect throttle sensor which I cleaned with no change. Put some injector cleaner in tank with minor improvement. Wondering if distributor module has gone yet again. Still playing up so I suspect head gasket and do a comp test. Compression fine 180-190 each cyl but all the plugs were consistently white when I pulled them out. So its gotta be running lean I think & running hot adds up. No manifold leaks as all been tightened and checked. I'm thinking bad fuel. Prior to all this I changed to buying ULP from cheap independent servo. Only 10ltr left in tank so I go fill up with ULP from normal Caltex and not independent. Full tank 60ltr of fresh ULP. The more I run it the engine is returning to normal.
So I've checked receipts and made sure I didn't put wrong fuel in, all say ULP. Looked into E10 which it says can use in this engine, however I'm reading will make engine run lean, run rough, hard starting, attracts water and dislodges deposits in fuel system to block filter. So I'm thinking I must have got a load of E10 or similar instead of ULP.
Anyone had these problems or bad fuel to confirm please?

I rebuilt the top end on a 91 Honda Civic engine for my son last year. Soon after he started using the car, he complained it was hard to start, stalled at intersections, or just died altogether. It turned out that, after several hours checking and testing things , he bought a bad batch of fuel from a servo selling cheap fuel. I drained the tank, put in 98 RON and it ran perfect.

IMO I would stick with using 98 RON as the engine runs smoother, starts easier, and keeps the injectors clean. The small additional cost for the fuel is offset by the extra mileage you get out of the tank. I tested this using 91, 95 and 98 RON over a number of months.

Well the problem is back again after I overheated the engine the other day. Managed to cook the transmission oil and put it in limp mood. I've had the tranny serviced and flushed, put a half bottle of injector cleaner in the tank, filled up with reliable fuel and taken for a drive. But the engine is running like crap in particular if you point the car uphill. So I'm changing the fuel filter to start with and if that doesn't do it I'll be checking fuel delivery and pressure to the injector rail and maybe changing the fuel pump. I'll see what happens as I'm getting pi---- off with this....

Changed filter under car, caused big air lock that I had to bleed out at the rail. Ran fine until it heated up then totally died and had to get towed home. I reverse blew out the old filter and a lot of crap came out. Going to pull the pump/sender unit from tank and clean the other filter. Also killed 2 batteries trying to start it so lots of charging to do. Discovered dizzy clamp has broken and timing might be out so just trying 1 thing at a time until it revives...damn frustrating

Post job edit: Apparently the air lock can be removed by priming the pump many times with a turn of the key for 5 secs between off & ign, no need to start. Air is bled off to the return line. Saves bleeding at fuel rail.

Update: Filter sock on tank pickup pipe checked and cleaned refer: ecu-fuel-system-eec-f21/eb-fuel-pump-removal-t131994.html

Last edited by acko on Sat Mar 25, 2017 7:34 pm, edited 3 times in total.

So I fixed the dizzy clamp and tried setting the static timing with the diagnostic connector pins bridged and cranking it. Couldn't get the timing light to work on any but lead no 2. So I figure must be the cap. Switched to another cap (used) and now only lead no 1 works with inductive pickup on timing light. So still thinking cap, but as no 1 is giving me flash, I do the static timing to 10btc and clamp the dizzy. Still wont start, cough, splutter, nothing but crank. So I check the +/- connection at coil and discover that when it cranks, there is no pulse from the TFI module. So yet again, 14 months after last one, its blown the TFI module in the dizzy, proper Bosch one. So I'm going to change the cap as well as the TFI module just to be safe.

Back on the road again. Changed TFI module, distributor cap and ignition coil, replaced distributor clamp, reset base ignition timing

see auto-electrical-forum-f89/tfi-module-replacement-no-4-in-as-many-years-wtf-ebii-4-0-t132005.html

Last edited by acko on Fri Mar 24, 2017 2:20 pm, edited 1 time in total.

Thank you for your updates. This will help people in the future .