New Engine - Major Hesitation

[f0xy]

Its a 172 Ph1 engine, freshly rebuilt head with new gaskets etc, new belt etc. Timed up perfectly with my tools, checked numerous times so im 110% certain it is not that.

When cranking to start, sometimes it will fire straight away, and proceed to idle fine - others it will crank and crank and crank, splutter a bit then fire up and idle. When it does splutter, you get a sort of popping from inside the engine/inlet, like a sort of backfire/missfire.

TDC Sensor is brand new, Lambda is known working and fine, CTS is brand new, Spark Plugs are new.

When it does fire up and its idling, if you give it ANY throttle movement what-so-ever it will cut out/attempt to stall, although if you let off quick enough it will try and recover itself...

I thought it was a TPS issue, so I swapped it from my working engine - but it made no difference at all, exactly the same problem.

Not tried coilpack or leads yet, but has anyone had any similar issues with hesitation?

 

[Russ_16v]

hmmm, air temp sensor? I had one fail and mine wouldnt run at all, id check for air leaks mate (not doubting your work) like the rubber bung on the inlet by the t/b

 

[Donny_Dog]

Its a Ph1 engine in a Ph2 or just a straight ph1 swap? Did you use the old known working coil pack and leads? They are in the correct order?

 

[f0xy]

I thought it could be an air leak somewhere, but checked it over. The fitment sticking out of the inlet near the TB is connected to the fuel pressure regulator with a piece of vacuum hose..

Its a Ph1 engine in a Ph2 or just a straight ph1 swap? Did you use the old known working coil pack and leads? They are in the correct order?

The engines in someone elses Mk1 valver shell - Yep the leads are 100% in the right order, coilpack could be dodgy - going to try a spare working one tonight with another set of leads.

 

[Donny_Dog]

Could also be fueling. Try the other pressure regulator sensor (if you have one) and check each sensor to the injectors.
You're getting sparks from the plugs too? plenty of things to be double checking tonight!

 

[f0xy]

Yeah, well the wierd thing is we had it running a week or so ago (no hesitation though) and it would rev up perfectly, no issue. We had to strip it down again as there was an oil leak from behind one of the cam pullies, some of the fresh sealant from the rocker cover seemed to be leaking.

After it was all stripped down, re-sealed and rebuilt - then timed up again and checked its had this problem. Weather its coincidence the coilpack has f*cked up or something else, who knows.

 

[Donny_Dog]

coincidence is unlikely, I always think the same as you.

Check, double check and tripple check. Its the only way. If its been running fine prior, it is just something you've missed the second time around - If you have faith in your timing!

Its either plug, coil, lead, sensor or a hose. She wants to go, but can't, so its back to basics for ya lad.

 

[sideways danny]

sounds ignition related

 

[Donny_Dog]

Did you get it sorted Foxy?

 

[Fred@BTM]

i'm going to say timing TBH dude

 

[f0xy]

Timing was spot on checked it all again.....

Put my spare coilpack on and it fired up fine, seemed to be ok - but it was still pissing out oil from behind the dephaser, just like last time.

Stripped both pullies off, popped the dephaser seal out of the head and it looks perfect. Decided to fit my spare dephaser pulley and re-time it all up which went fine. Started it up again, STILL pissing out oil from behind the dephaser.

Now, I know the rocker cover is sealed perfectly, as we've had it off once and re-done it all - exactly the same as ive done my own engines 10+ times in the past 18 months, and ive never ever had a leak... The only thing it can be is the seal? Its from a factors head gasket kit, not a genuine Renault seal - starting to wonder if thats the problem!

 

[Fred@BTM]

yup factor seals don't work on them

 

[f0xy]

Grim. Better get a seal kit ordered from Renault then I guess

 

[Chesh]

So it was coil pack then? Im having a sort of similar problem

 

[f0xy]

Couldnt really tell, only ran it for about 15 seconds then turned it off due to the oil leak. Once thats fixed we'l be able to tell if its sorted it or not..

 

[Guppy]

Bad times.

In fairness, You have the patience of a saint!

I would of thrown a match at it along time ago!

 

[f0xy]

Its not mine! lol

 

[Guppy]

Oh, i see :-/

You still have alot of patience regardless!

 

[Jonny1*2]

Its not mine! lol

who's block is this one Jord? Another mk1 172 on the horizon?

 

[f0xy]

Plenty out there now and quite a few in the process. This engine problem is with AdamAnderton's on here...

 

[Jonny1*2]

had a feeling he was going to do that. Fingers crossed the Gb mount doesnt go on this and fubar the engine

 

[Laine_16v]

Mine will be done very shortly too

 

[AdamAnderton]

car is now sorted and is running fine, First post on page 29 is a vid of it running fine
http://www.cliosport.net/forum/showthread.php?t=450405&page=29

The problem was the tb