1.4 Volvo - I need help (idle solenoid need a new one)

[mat_91]

you can just pull the tip off with a pair of pliers and that does it

[valman]

got a new one off j340glt yesterday, car runs much better now, but still seems to hunt a bit now and then. i havent set the mixture up 100% but its bang on 950 - 900 rpm on idle but sometimes still drops a bit. managed to break the breather t piece on the rocker cover which doesnt help vacuum wise but i plugged the broken hose up with a bolt which seems to have made it run better. any idea what else could be causing the idle hunting?
also i had a hunt around a scrapyard the other day for bits and i noticed that renault 5s have an identical renix unit ( didnt check part numbers etc ) but looked identical to the volvo - could that be a worthy replacement if mine is packed in? or would they have different ignition maps on them?
cheers for the help so far

[mat_91]

haha i told you so lol and they do have different maps in them as the 1.4 in our volvos is a hevily detuned revision of the r5 unit

[valman]

haha i told you so lol and they do have different maps in them as the 1.4 in our volvos is a hevily detuned revision of the r5 unit

hmmm i wonder what an r5 renix will do then, might try get hold of one cheap and give it a go haha

[jtbo]

I think most of idle hunting issues are because some sort of air leak, vacuum or some another kind.

When car is idling, can you make it stall by placing hand on top of the carb barrel? If it runs just better when you do that, then it must have leak somewhere, either vacuum piping or carb base, those would be first ones to check, nothing cracked, nothing worn so that they are loose, like throttle butterfly axle?

You can even do partial block to top of the carb and see if it runs better, if it does, then it just has leak somewhere, this is good to test if blocking fully makes it stall.

Vacuum hose to brake assistant servo thing can be looking fine from top but be bad from inside, causing a leak, I have heard.

Oh and one more thing, is your vacuum hose from valve cover t-piece been replaced at some point? That hose should have 1mm restrictor in it, if hose has none, then it causes poor running for sure. Just thinking this as blocking that hose had made it running bit better.

If still no clue, start taking everything apart from front of engine bay and work towards back of engine bay, every vacuum pipe that is.

You can also get some instant gasket, that is meant for use with petrol and put that between carb base and seals if that is the problem (problem comes with over tigtening of carb screws), but that is just quick dirty hack to get it working for a while, real solution is to straighten surfaces, table, piece of window glass or thicker and wet sand paper are required for job to make car base straight again. Manifold side is more problematic to fix, I believe.

If you use instant gasket, don't use too much of it, you don't need 3mm layer to cure less than 1mm of gap, use finger or similar to spread applied stuff so it is evenly thick layer of about 1mm, beware of letting stuff to go too much inwards as it might get into engine or block some holes needed to be open at bottom of carb or such. I have been happy with Plastic Padding made red instant gasket, it has been easy to remove, which is good when one needs to do a proper job.

[valman]

thanks for the great info as always jtbo! i think youre right - instant gasket can be the only cure although it seems to be missfiring when the revs drop and ive checked for leaks using wd40 applied to carb base/etc and it didnt make a difference to running where as ages ago when it had a leak it did - tax runs out today anyway and im hoping to get another car for runabout duties and will be taking this off the road to have some work done it. just reluctant to pile money into having a 1.4 when i could have a 2.3

[jtbo]

thanks for the great info as always jtbo! i think youre right - instant gasket can be the only cure although it seems to be missfiring when the revs drop and ive checked for leaks using wd40 applied to carb base/etc and it didnt make a difference to running where as ages ago when it had a leak it did - tax runs out today anyway and im hoping to get another car for runabout duties and will be taking this off the road to have some work done it. just reluctant to pile money into having a 1.4 when i could have a 2.3

I have never got any reaction to starter spray or WD40 either, not even when I had over 1mm gap between carb base and plastic piece that is there in 360.

Also it had quite bit of banging at engine braking.


1.4 can be quite bit better as daily than anything with bigger engine, it would just require quite a bit of aerodynamic modifications, some Nokian winter tires (world's lowest rolling resistance) and such, small petrol consumption but performance would be near to what bigger engine versions have.
I have studied that over 40% less losses is very much possible, that means over 40% more power to make car go.