Lumpy running DX

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jonGTX
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Lumpy running DX

Post by jonGTX »

So you may or may not have heard about the red shed melting the top of its rotor arm on the way to Tatton Park last weekend, managed to get it home on a 2nd hand rotor that wasn't an exact match but have since put a brand new correct arm in

However, despite running ok-ish on idle, it sounds lumpy and slightly laboured on revving, leads/cap/arm are new, going to replace the plugs this weekend, if that doesn't work, is it new dizzy time? Or is it just the ignition timing has slipped out?


Rocco Mafia Car of Choice 2010
1989 Helios Blue Scala 16v *sold*
1994 Mulberry Corrado VR6 *sold*
1991 Tornado Red Scala GTi Engineering RE2000 8V *sold*
1991 VW Polo G40 *sold*
1990 Pearl Green Scala
2020 VW Polo GTi
duggers
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Re: Lumpy running DX

Post by duggers »

Could be the plugs fouled during poor running so replacement is first call.
Cant see the timing 'slipping' in the circ's you describe. Once you do the plugs if there is still an issue test the hall sender and the ign' module as per the Haynes book of lies....


Apparently the dreadful paint on my Rocco is PATINA....
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james butler
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Re: Lumpy running DX

Post by james butler »

check the coil isn't tracking out.
i had a burnt out rotor once and after i replaced it i had a lumpy idle and misfire.
when it was dark you could actually see the spark tracking from the coil turret around its base (it had cracked in the heat) and jumping to the negative terminal.


I dont mind project cars but I HATE SANDING!!!
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jonGTX
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Re: Lumpy running DX

Post by jonGTX »

Picking up some new plugs in the morning, Bosch WR7LTC+ ones, can get four from GSF for £11 whereas the NGK BUR6ET I was using are £25 a set so will start from there really, the only things that have changed are its run on a knackered and slightly different rotor arm and the caps been off four/five times so am hoping its just what duggers said and that the plugs have fouled up


Rocco Mafia Car of Choice 2010
1989 Helios Blue Scala 16v *sold*
1994 Mulberry Corrado VR6 *sold*
1991 Tornado Red Scala GTi Engineering RE2000 8V *sold*
1991 VW Polo G40 *sold*
1990 Pearl Green Scala
2020 VW Polo GTi
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jonGTX
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Re: Lumpy running DX

Post by jonGTX »

New plugs done the trick, sweet as a nut again, cheers for the assistance boyos :beers:


Rocco Mafia Car of Choice 2010
1989 Helios Blue Scala 16v *sold*
1994 Mulberry Corrado VR6 *sold*
1991 Tornado Red Scala GTi Engineering RE2000 8V *sold*
1991 VW Polo G40 *sold*
1990 Pearl Green Scala
2020 VW Polo GTi
duggers
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Re: Lumpy running DX

Post by duggers »

That's good news.
I have a saying I use when delivering the training I'm involved in; If it quacks and it waddles guess what, its a duck.

Sometimes simple is the answer.


Apparently the dreadful paint on my Rocco is PATINA....
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mr.brown
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Re: Lumpy running DX

Post by mr.brown »

Bosch plugs for a DX engine should be WR7DC+. The tip of the "L" is totally different (and they are twice the price!).

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jonGTX
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Re: Lumpy running DX

Post by jonGTX »

I stuck with ngk's in the end, it seems to like those


Rocco Mafia Car of Choice 2010
1989 Helios Blue Scala 16v *sold*
1994 Mulberry Corrado VR6 *sold*
1991 Tornado Red Scala GTi Engineering RE2000 8V *sold*
1991 VW Polo G40 *sold*
1990 Pearl Green Scala
2020 VW Polo GTi
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