Hi Short story .......... now it's on points. Long story ........ tried a PowerSpark module in my Bosch dizzy last spring (fitted by a garage), It was ok at first, did about 700 miles, but still felt sluggish. Then coming up the M5 last summer, it started to get real slow - hot maybe, as I just got into a bit of traffic jam,, then it back fired that loud I thought someone had driven into me. Got off the motorway and just about got it home, - backfiring and running bad all the way, heel and toeing brakes and throttle. Went back to the garage, they said it was a faultly module, and replaced it. It was ok for a while then the back firing started again. Back to the garage !! They said my injection system didn't like the electronic module, so put it back on to points. On points, I still get a bit of a pop/backfire on deceleration when going down hills, but thats possibly because my exhaust is'nt great. but no where near as bad as when the electronic ignition was on it.
@Patrick Nguyen @77 Westy Thanks, I got in the Noisy Cupboard yesterday (I like that analogy, lol) Engine at running temp, vacuum disconnected off the dizzy vac canister. Tick over set to 7.5 BTDC (as per the specs from my dizzy part number) 022 905 205 S Did my best with my head that close to the engine and pressed throttle lots, as @mikedjames said......loud Timing was on 28, probably would have gone up more if I'd have throttled it more, but was guessing the RPM. There was suction from the vac pipe that connects to the dizzy, on my finger. Last time I had the dizzy off (last summer) I did blow/suck the vac canister, and it seemed ok. So all ok ????? It did appear to be too hot, I was sitting on the floor behind it, I could feel the heat wafting from under the bumper, but probably because it was stationary and no air flow to it.
Thank you for replying I'm pretty sure the flaps are open, the thermostat cable holder bracket is upright, meaning they are open ???? Did your engine totally blow up, or did it just start to fail? I'm preparing myself for what might happen. Do I get a big bang and then it's game over ?? Good idea about a temp gauge, I've got a Gene Berg dipstick temp sensor some where from 20 odd years ago, off my Beetle. I'll dig it out this afternoon and calibrate it. Probably a lost cause though, because it must be getting too hot
Not sure what it should look like on the thermostat as I don’t have a T4 engine anymore. But someone will let you know on here I’m sure. Yes it broke down completely on the way to Stanford Hall years back. It blew a valve. I was caning it a bit mind you. But you live and learn! It will stop you guessing if you do get your temp gauge up and running. I can’t remember what carb/injection system you’ve got but if appropriare I’d get the carb set up properly both co and fast idle too and go from there.
OOOUUUH, I forgot to say amongst all my anxious Babbling. When I had the air filter/AFM box off, to check the spark plugs, I noticed oil residue all round/inside the metal part of the AFM that fits to the S boot. When I replaced the S boot last summer, the oil was definitely not there then. Another sign of it being too hot ???
Hi, 40 year old standard Cali exhaust inc CAT, like this, ignore the colour circles, they are parts I'm looking for to get the exhaust replaced.
Popping on the overrun may just be a small hole in the exhaust. These engines blow a lot of hot air normally think 10 plus cubic feet a second at full throttle . Or what a 2.5 kW compressor does in a minute but every second. I would get a cylinder head temperature thermometer. Engines that eat electronic modules may have a coil that breaks down at high temperatures when the HT spark jumps back to the CB terminal. Or a loose spark plug wire making the HT secondary voltage go high that makes the primary voltage go extra high. My most recent electronic ignition failure was a rev limiting effect where if I hit over about 2000 rpm it killed the spark then as the rpm dropped it would light up the unburnt fuel in the exhaust with a massive bang. I drove about 4 miles in heavy traffic like that. When it was running between the backfires it ran perfectly. This kind of thing makes holes appear in the exhaust.
Popping on overun is almost certainly a gap somewhere in the many joints on that exhaust system, I ditched mine for a triangle flange empi as that's all that's available at affordable cost, runs fine on it
Agreed about the exhaust @Flakey , I've got a replacement but it's going to take some serious heat to get the 40 years old crusty bolts off the heat exchangers. but no point doing it if my engine is dying I'm gonna nick one of your Scubbies when your not looking at TE ,lol and the magic Scubbies fairies will visit in the night and fit it to my bus, whilst we all peacefully sleep
I ran 15w40 in my type 4, it ran better on it than on the 20w50. The thicker oil made it harder to rev and almost sluggish Electronic ignition will work fine with a type 4 on fuel injection. Pertronix is the way to imo. Heat from the engine underneath is fine,feel the topside fan housing when you think it feels too hot, with the engine running the fan housing should be cool to touch. Not sure if your engine is GD or GE but the valve gaps may need doing. If GE they will be hydraulic and shouldn't need touching. Don't touch the AFM screw anymore!
Hi, thanks for the reply. Before the 15w40 it was on SAE30, not sure if i've done the right thing getting the garage to change it to 20w50 then 1st proper drive on the 20w50 will be to TE, so I'll see how it goes. Yeap, top of fan housing feels cool....obviously it's red hot after I stop, also did the dipstick feel/touch test when engine was hot, and it wasn't unbearably hot. So I'm at a loss with my limited knowledge, why it's over heating, as you've seen in the pic's of my plugs. It's a GD engine, and the garage said they'd done/charged me for adjusting the tappets 700 miles ago. Also nearside push rod seals replaced, which are now leaking more than before they replaced them Ok, won't touch the AFM anymore, hopefully someone at TE can test the gases to see if it's too rich still ??? The oil residue coming from the S boot into the AFM is a bit worrying. If you remember, I bought the S boot off you last summer, and there was no oil in it when i changed it back then. thanks again.
and I'm truly sorry to you all about whining so much, it's been going on for a year now, and sending me in sane....and skint !!! camping, cider, giggles, bacon........ well and truly needed
