Rovergauge TPS Reading

[Technoholic]

I just installed RG and had a quick play with it. I can't see anything obvious that's leading to my misfire feeling under partial load, but I'm only just learning about RG so I might be missing something.

However when looking at the throttle position readings, I noticed that it reads 0% at it's lowest, or 5% absolute, but when fully depressed, it reads a maximum of 67% in both corrected and absolute. Does this sound like an issue?

[bobfather]

Yes that is an issue though I don't think it would be related to your missfire. The TPS can be adjusted by rotating on its two screws. you may need to file out the TPS fixing holes to allow adjustment. Be warned, the three wires become very brittle over time and several owners have found them breaking off at the TPS end.

[Technoholic]

ok thanks, I'll look into that. I need to figure out this misfire issue though. I am changing all the plugs this weekend and removing the plug extenders. I'm going to Racetech tomorrow to pick up some bits including a new amp hopefully, and probably a new coil. Stepper motor was cleaned last week. Coolant temp sensor I know can cause this too but the temperature readings in RG seemed fine although they didn't match the dash gauge at all, so I guess I need a new temp sender too.

[LLantrisant]

dash & ecu temp. sender are 2 different senders....so they never match....the readings might be close, but never identical.

[Technoholic]

mine were about 25 degrees apart although when driving the dash does eventually get to the 90-100 range. Maybe it's just slow

[spitfire4v8]

Remove the plenum intake hose and get someone to press the throttle .. see if your butterfly is opening fully. My guess is it's not.

[Technoholic]

I hadn't considered that, could that be causing the issue of the misfire feeling or just the reading of the TPS?

I take it the butterfly should go from vertical to horizontal at fully open?

[bobfather]

You are focussing on fuel & air for your missfire, Yes they can cause poor running that may feel like a power hiccup but a hard missfire is far more likely to be HT related, leads, extenders, coil, ignition amp, etc.

[Belle427]

Info on settings
https://www.pistonheads.com/gassing/topic.asp?h=0&...

[Technoholic]

Well actually I think that it does feel more like a hiccup, very noticeable but there are no pops and bangs associated with them like in a misfire

[N7GTX]

Remember that with 8 cylinders a misfire is much less felt than a 4 cylinder engine. If you do go ahead and replace all the HT components - amp, coil, leads, dizzy cap, rotor arm and plugs - and remove the extenders, I think you'll find the hiccup/misfire disappears.

[bobfather]

N7GTX said:

Remember that with 8 cylinders a misfire is much less felt than a 4 cylinder engine. If you do go ahead and replace all the HT components - amp, coil, leads, dizzy cap, rotor arm and plugs - and remove the extenders, I think you'll find the hiccup/misfire disappears.

^^this^^

HT is where your missfire comes from. Start with the obvious, extenders are an obvious starting place, how old are your HT leads, is there any heat damage at the plug ends. Don't use ebay HT leads as these can missfire from new. Ignition amps are becoming an issue now due to age, they get too hot. The engine bay gets hotter than most cars and so components age prematurely. I have rovergauge and use it often but I would not use it to find a missfire.

[Technoholic]

The dizzy cap and the leads were changed recently by the previous owner. The Rest of the system I have no idea of age. After this weekend I should have the parts for new coil, amp and plugs. I will be removing the extenders and using the heat socks that I have with BPR6ES plugs. If that still doesn't help I will change the cap and rotor arm. I have emailed Distributor Doctors to find out about their replacement arms as these are supposed to be much superior to the current Lucas stock, as good as the original Lucas ones form what I've read.

[Coefficient]

I was surprised how oxidised my dizzy contacts had become. A gentle sand paper seemed to fix my misfire, touch wood.

[blitzracing]

Morris Minor or Mini?

[Technoholic]

Chimaera

[Coefficient]

[Belle427]

Technoholic said:

The dizzy cap and the leads were changed recently by the previous owner. The Rest of the system I have no idea of age. After this weekend I should have the parts for new coil, amp and plugs. I will be removing the extenders and using the heat socks that I have with BPR6ES plugs. If that still doesn't help I will change the cap and rotor arm. I have emailed Distributor Doctors to find out about their replacement arms as these are supposed to be much superior to the current Lucas stock, as good as the original Lucas ones form what I've read.

Did you get any news regarding the amps?