Starting problem.... but cold

[rigga]

Got a problem that ive had since i purchased the Griff...... on a cold start the engine is a pig to fire,it catches then stutters and splutters so much that if i dont add throttle and hold the revs for approx 10 seconds at 1500-2000 rpm it will die,and then be even harder to restart,or even flood the engine completly.....once ive added throttle and then let it idle,its fine,and in all other respects runs fine,except on the odd occasion (twice) when very hot it runs rough and attempts to cut out..... possibly the later is something breaking down with the heat,but its so intermittant im not that worrried about it,the cold start issue though affects it every time i use the car...today i didnt catch it in time,and the plugs flooded,and obviously wouldnt start,took them out (two month old set) and fitted the original set to get it to run,my initial thought was a faulty coolant temp sensor reading incorrect so the ecu is adding too much fuel on initial atart up,but im not sure now because as i say,after the initial few seconds of poor running,its fine otherwise...... any thoughts before i start throwing parts at it?

Martin

[GreenV8S]

It's worth running a meter over the temp sender and other sensors, best to do it from the ECU connector so that you include any wiring faults.

[Troogly]

... it might be the Cold Start Injector (although that wouldn't explain your hot start problem). The Cold Start Injector is there to squirt a little extra fuel (a few seconds) to assist starting from cold.

It's easy enough to check. Simply unscrew the two bolts that fixes the Injector into the plenum. Keep the electrics connected to to the injector. Then on a cold start turn the ignition on. With someone turning the key you should be able to watch if there is a fine spray of fuel coming from the injector. If its not - then either the injector is not getting a signal to dispense the fuel - or the injector is u/s - which is easy enough to change.

[Toma500]

I had almost exactly the same problem last year and it was the engine temp sender , well changing that cured it . but not before i had spent a lot of money changing the stepper motor and the ignition amplifier . try changing the sensor first i think they are reasonably cheap and easy to do.

[rigga]

GreenV8S said:

It's worth running a meter over the temp sender and other sensors, best to do it from the ECU connector so that you include any wiring faults.

Read the section regarding this in the bible,trouble is in my single garage its very tight access wise on the passenger side,so getting to the ecu to check the loom as well is problamatic...... wouldnt know the resistance of the sensor on its own by chance would you?

Troogly said:

... it might be the Cold Start Injector (although that wouldn't explain your hot start problem).

I have no hot start problems,car has the modwise kit and its never failed to start when hot..... problem is only on first cold start

Troogly said:

watch if there is a fine spray of fuel coming from the injector. If its not - then either the injector is not getting a signal to dispense the fuel - or the injector is u/s

Again this would be an issue if the car was failing to start due to lack of fuel,this is not the case as its plainly overfuelling and fouling the plugs very very quickly..... disconnecting the cold start injector may be of help to determine if the thing is simply dumping too much fuel in by being stuck open etc...or the problem lies elsewhere...

Toma500 said:

I had almost exactly the same problem last year and it was the engine temp sender , well changing that cured it . but not before i had spent a lot of money changing the stepper motor and the ignition amplifier . try changing the sensor first i think they are reasonably cheap and easy to do.

This as i said was my original thought... any part number you can quote so i can poss source one local to me?

Thanks for the ideas....

[Barkychoc]

Troogly said:

... it might be the Cold Start Injector (although that wouldn't explain your hot start problem). The Cold Start Injector is there to squirt a little extra fuel (a few seconds) to assist starting from cold.

It's easy enough to check. Simply unscrew the two bolts that fixes the Injector into the plenum. Keep the electrics connected to to the injector. Then on a cold start turn the ignition on. With someone turning the key you should be able to watch if there is a fine spray of fuel coming from the injector. If its not - then either the injector is not getting a signal to dispense the fuel - or the injector is u/s - which is easy enough to change.

Doesn't this apply to the flapper system and this is Hotwire?

[spend]

Barkychoc said:

Doesn't this apply to the flapper system and this is Hotwire?

Most definitely so

Once you get into the habit of touching the pedal when starting all sorts of weird things happen IME and diagnostic wise all deals are off

[Toma500]

Engine temp sensor £20.70 at clevor trevor part no EO376 sorry dont know the Rover part no.

[rigga]

Toma500 said:

Engine temp sensor £20.70 at clevor trevor part no EO376 sorry dont know the Rover part no.

Thanks for that.... i ordered one from famous four late last night for around six quid,so will try that,was flicking through the service history and noticed the leads,cap and rotor arm are more than a few years old also,so ordered new from the same place,very reasonably priced,will try them and see how it goes

spend said:

Once you get into the habit of touching the pedal when starting all sorts of weird things happen IME and diagnostic wise all deals are off

I know what you are saying,but without adding throttle the engine will die every time..... more investigation needed

Edited by rigga on Tuesday 27th January 21:41

[rigga]

Right,an update on the problem... wet plugs were removed,and taken to work where i dried them out with a heat gun,and cleaned up with a wire brush,then re installled in the engine...having read through the service history of the car,the ignition system seemed to be several years old,so i thought it best to renew certain servicable parts that were probably coming to the end of their life anyways,so new copper core leads,rotor arm and a dizzy cap,all lucas items were ordered from famous four website,at a very reasonable cost,plus a coolant temp sensor that i suspected was faulty for £6.... try getting one of those for a tvr at that price (£20 at a well known trv parts site)..all arrived in two days flat and couldnt be more happy with the service...so today i fitted the bits,slight hiccup as i just ripped all the leads off the cap previously without marking number one .....thought id be ok as there was a diagram in the bible showing relative positions for the lead set,compared to the cylinder position (page 67 by the way)trouble is its wrong! or at least the vacumn unit position,and therefore the lead numbering is for a preserpentine engine i believe,not a later serp engine,a little panic set in cursing my impatience...luckily though two pages back there is a photo of a serp dizzy and i could work out the position and sequence from that,also removed the stepper motor and cleaned that up,so all ready to fire her up then...... and she started and idled ok,no throttle input needed,slight fluffy throttle responce till some heat generated,but more than happy that the cold start problem has gone,cant pinpoint exactly what it was,as i replaced a few things all at once,but didnt want to try one thing at a time,to find the fault still existed,and the engine might flood again,but end result is the main thing,thanks for all the input.

[GreenV8S]

The lesson with the HT leads is to replace them one at a time, or mark the position of the #1 lead on the dizzy body. The order is always the same, but so once you know where the #1 lead is you can always get the others right. But the #1 lead can go in any position, and the dizzy body can go in any orientation, so it's impossible to tell just by looking at a book or even comparing another engine, where the leads are supposed to go on yours.

[rigga]

GreenV8S said:

The lesson with the HT leads is to replace them one at a time, or mark the position of the #1 lead on the dizzy body. The order is always the same, but so once you know where the #1 lead is you can always get the others right. But the #1 lead can go in any position, and the dizzy body can go in any orientation, so it's impossible to tell just by looking at a book or even comparing another engine, where the leads are supposed to go on yours.

Perfect sence in the cold light of day...... unfortunatly i know better ....turned out all right in the end even with my desperation to strip the engine of its parts