Hello from a Newbie with a Project

That grot doesn't look bad at all Greg. I will post pics of the breaker on my next visit to it, that will make you feel a whole lot better trust me!

Yes as for running issues, can you check the front fuel pump is running?

Thanks Martin. That would be good for reference and keeping up morale whilst I am stuck on this engine running issue.

Checking front pump running continuously is on my list, problem is, I can't keep the engine running and be at the front of the car at the same time without an assistant.... and so far, no one has been around to do the job! I take it the front pump cuts out at the same time as the high pressure one does. i.e. when the engine stalls and the crank sensor notices? If the engine is running, is it easy enough to tell the front pump is working just by grabbing it? In any case, would my symptoms fit the bill of a faulty front pump i.e. no idle, rich running but no problem when revving the engine?

I have had NO luck in pressure testing the fuel lines. I ordered a new gauge in time for this bank holiday weekend, sure enough it arrived in time but, unbelievably, the only bit of the kit I really need, the T-piece, was missing from the box...... aaarrgh, so annoying! I did find that the return fuel pipe from the bottom of the FPR was kinked really badly so replace this today.

I did get the replacement ISCV to test. Swapping this in and the engine runs constantly around 3k revs. Ok, so this one must be stuck wide open? Swap back to the original, it starts, runs for about 5 seconds (can hear the valve move quickly one way though) but then gets progressively richer until stall. So the replacement from eBay I suspect just doesn't work. As for the original, is it fair to say that sometimes they will adjust correctly for big changes but then can't handle smaller subtle changes when required? I think next, since the ISCV has such a profound effect, I need to undo the tabs, open her up as Ryan suggests and see if I can get a better result. As a matter of interest, I took a voltage reading from the ISCV connector with ignition on but car not running and it was around 2.8V. At least I know there's a signal of some sort coming through the loom, does this voltage sound sensible?

Could really do with a fuel pressure reading though to know what's really going on.

Still no luck tracking down a replacement FPR should it be necessary. Haven't heard back from the local Renault dealers so I assume they didn't get anywhere.

Future plans for this car once the engine is running is to get the pedals back on, bleed the brakes and take it to my friendly MOT station and see where we're at. If that works, will take the car to Snetterton as it sits, old tyres and brakes and all and see how it handles a day on track at it's worst. Call it a shakedown to see how the motor and trans handle things and get an idea of the potential that lies within. If it goes well, then I can start working towards track focus upgrades, not forgetting the likely welding required and a cage for safety. Speaking of which, anyone with experience of installing a cage in these? Any off the shelf stuff around? Any solutions that can retain rear seats? These are the dreams that keep me trying

.

Couple of cage options but nothing 'off the shelf' I have a welded in version and one of my customers has just had a bolt in version installed .You are looking at around 2k + fitting for full FIA spec .

Ahh, so it should still idle with the valve shut, it just adds more air, as my plate is set bang shut, i.e kink the ISCV hose and it dies.
I also assume IDC is another term for ISCV .............so if I opened the plate up, would the ECU then adjust the ISCV and bring the idle back to where it should be?
I had a R21 Ti that had a water temp sensor fault and that showed as a ECU fault light, basically it seemed to be in the warmed up state all the time so you had to let it warm up before it would drive anything like.
My GTA does seem a little rich when its cold, but the stat was a opening up quite quickly so I put a new one in I tested back to back on the hob and it was a lot snappier, i.e opening later, but quicker to full open then snappier to shut as the pan temp decreased, with the added bonus of popping in an egg while I'm at it.
With the ECU map bodge I was deffo lean 'cos after a blast the tail pipes were light grey, but this year after I have fitted it up I will try and get it running perfecto standard.
With these cars it always seems to be multiple reasons for a fault!

There is an adjuster screw on the throttle body to set the plate closed position .It has a locking clamp that more or less covers the thing .

Haven't had a chance to do any more with the car over the past few days.... work getting in the way of what I really want to be doing! Still no fuel pressure tester either! Come on Royal Mail.

Mulling all this over as one does, realised I have never checked the air filter. Sitting in a field for so long and where it's located, could be all sorts in there blocking it up. OK, so really simple question, what's the easiest way to get to it to check? From underneath or through engine bay and what else needs to be removed for access?

[BIG_MVS]

Air filter to the right of the engine bay. You can open it from underneath and 3 clips hold the base in place. Remove and the air filter is there. Loads of options for new as it's a Renault 25 and 21 Item.

Air filter to the right of the engine bay. You can open it from underneath and 3 clips hold the base in place. Remove and the air filter is there. Loads of options for new as it's a Renault 25 and 21 Item.

Thanks for the pointer Martin. Now I just need the rain to stop pi**ing down and I'll have a go. I'm too Southern to work in that weather Fuel tester arrived too. Fingers crossed.

Finally managed to get a fuel pressure test done and things don't look quite correct. This is all a bit new for me so would like to check the method / assumptions used before jumping to any conclusions.

This is a 1988 car with a single FPR. The ASSUMPTIONS are as follows:-
- the fuel connection at the bottom of the FPR is the return to the tank
- the 2 hose connections on the side of the FPR are the returns from the fuel rails on each bank
- pressure testing can be done by T-ing into either of the return hoses mentioned above and the reading should be the same either side at any particular time.
- The fuel pressure should be around 3.2 bar under most conditions.

TEST
Testing was done with the original FPR and its vacuum connection in place. The Idle Stabilisation Control Valve (ISCV) active was connected and plumbed in. The ignition was switched on and the fuel pumps allowed to prime and stop before starting the engine (Fuel pressure around 3 bar after prime and held steady). Throttle was left in idle position for the whole test.

RESULT
At first, car idles OK, pressure reading is :~2.4 bar. After about 10 seconds, the idle speed begins to slow, I think you can hear the ISCV opening in an attempt to bring the idle back, thus fuel pressure raises to ~2.8 bar , engine struggle for a while then manages to recover normal idle, at which point fuel pressure drops again, cycle starts over but this time engine stalls.

For me, this just creates more QUESTIONS:
1) Does this make sense. Is it normal for fuel pressure to rise as ISCV opens?
2) Is it fair to assume FPR is knackered or do I need to investigate the fuel pumps further before changing the FPR?
3) If the front pump is not working, would this create the problem described and would the engine be able to rev so well when throttle opened?
4) Since I can hear the ISCV opening up as the idle drops, is it fair to say this part of the system is OK?

This should be a video link....
https://youtu.be/xjt1yJdkif0

(By the way, how does one embed a video?)

Going to crack on today and assume also that nothing is glaringly wrong with the assumptions made above or the test method otherwise someone in the know would have chimed in. I have a cheapo adjustable FPR handy so today, weather permitting, will plumb that in as a replacement and see if there's a change. Wont be the final solution for the car, but at least this might tell me whether the high pressure pump is providing the maximum 4 bar? that it should.

https://youtu.be/Xx7BD3HPWqU

She runs! Settles to a nice idle (slightly better when warm) revs up OK,with maybe the slightest hesitation from idle. This is running on a cheap ebay adjustable FPR with gauge though.

I have a new Renault FPR on the way and a new coolant temp sensor and still to fit the new distributor and rotor so hoping the combination of all these new parts might iron out the last few stutters.

As you can tell from the video, she's a little tappety when up to temperature. Sounds like it's either cylinder 4 or 5. The video makes it sound worse than it actually is as my camera was directly above the noise. How easy is a valve adjustment?

Also noticed for the first time that front radiator fan kicks in as the temp reaches 90C which is good news but perhaps the alternator is a bit weak? around 13.5 V at idle and maxing at 14.1 V by 2000 rpm. Normal?

Now I need to get those pedals fitted , bleed the brakes and go for a short investigative drive. Just need more time.

They do sound a bit tappetty anyway, but given the time the car has been sitting and the effort to make it right, it will be a good idea to set the tappets. this is not a difficult job, although on the RH bank some pipes and wires need to be moved out of the way.

On the charging side of things it will be OK. With the fan on at idle 13.5V can be expected. In ideal circumstances on load at revs, charge rate should be 13.9 - 14.2V. Glad you are getting it sorted.

They do sound a bit tappetty anyway, but given the time the car has been sitting and the effort to make it right, it will be a good idea to set the tappets. this is not a difficult job, although on the RH bank some pipes and wires need to be moved out of the way.

On the charging side of things it will be OK. With the fan on at idle 13.5V can be expected. In ideal circumstances on load at revs, charge rate should be 13.9 - 14.2V. Glad you are getting it sorted.

Thanks Alan. Sounds like the alternator is as expected then which is great news. I've been searching for the cold clearance settings for the tappets to no avail. Any idea what these should be? And is it ok to re use the valve cover gaskets or should I be ordering some ahead of time?

Changed all the plugs now and this has ironed out the last few misfires. On the driveway, she now idles and revs very well at any temperature.... so even though the new Bosch FPR has arrived, for now, I'm leaving my cheap adjustable FPR plumbed in until road testing. I have read a few comments to say that these motors can lean out a bit too much at the top end. If so, does upping the FPR pressure a little help to counter this issue?

Can't wait for the first drive. Optimistically within the week!

Inlet 0.10mm (4 thou) Exhaust 0.25mm (10thou) done cold. When I bought my car it had not had them done in 100 000 Miles, and really weren't all that far out. The cam has the smallest lift of any car I have seen. It only lifts the valve about 6.5mm. The Volvo naturally aspirated V6s have about 8.5mm.

Inlet 0.10mm (4 thou) Exhaust 0.25mm (10thou) done cold. When I bought my car it had not had them done in 100 000 Miles, and really weren't all that far out. The cam has the smallest lift of any car I have seen. It only lifts the valve about 6.5mm. The Volvo naturally aspirated V6s have about 8.5mm.

Thanks again, very helpful. I see you're in my favourite hemisphere.... I swear I was born on the wrong side of the planet! Have fond memories of some time spent staying on the South Bank about 10 years ago ... making much use of municipal BBQs and swimming in the lagoon...... Hope to make it back one day.