S4s rolling restoration project

[Chillidoggy]

Have you fitted your brake kit yet, Tom?

[tomcattom]

Not yet Ian, but it's the next thing on the list to do, alongside fitting Dave's suspension kit.

Now the car is running I want to spend some time in the "rolling" state over the summer to just enjoy it, rather than spending more time in the "restoration" state that it's spent the lion's share of its time with me in.

[Giniw]

9 hours ago, tomcattom said:

The cars and coffee meets are getting more and more common. There are some during the week, typically in the evenings. Never been to a weekday one myself, they're never close enough for me to make it worth driving to them after work. This one was a Saturday morning and very close by, so was convenient

(indeed before I edited my post I was surprised there were cars and coffee meets even during the work week ... that was until I realized you posted about this on Saturday, hence why I edited my post ^^. Anyway, thanks for the explanation since it appears there actually are car meets organized during the work week!)

Edited June 15, 2022 by Giniw

[Chefchen]

Hi Tom,

how satisfied are you with the Nankang tires? I also need a new set of tires soon and I've shortlisted the Nankangs too, but I don't know if they really go with the Esprit!?

Best regards

Stephan

[tomcattom]

I can't give a full verdict yet @Chefchen, I've only done 420 miles on them and due to the tracking still not having been done I've not really dared fully push the car yet, but initial impressions so far are positive in dry conditions at any rate. My friend who put me onto them in the first place is impressed with them on his TVR Cerbera too.

[tomcattom]

Another 12 months ticket on the car as of last Thursday, but it wasn't all plain sailing. On the way over to the test centre I noticed it had started to idle at 1500rpm. Luckily when I restarted it at the test centre it was back to normal, until I left and then was idling nearer 2000rpm on the way back. Fortunately I had my laptop with me and Espritmon revealed I was seeing around 10% TPS input without my foot off the throttle.

I spent a bit of time inspecting further with Espritmon today and it was seeing 0% with no throttle, but at full throttle I was barely getting over 80% registered, this despite me setting everything up properly when the new throttle cable was installed in the Spring. I decided to check the throttle cable setup first, I remeasured the clearance at the full throttle abutment on the throttle body and that was measuring the 0.1mm as per the guidance in EMH.3, so clearly the throttle cable is all fine. Luckily I had bought a spare TPS from RockAuto when I imported the new ECM last year so I put that on and immediately everything is reading correctly again and I have full swing from 0 to 100% showing in Espritmon. Nice quick fix thankfully.

Next on my list was the pesky boost situation again. I reinstalled the wastegate actuator solenoid before the cars and coffee meet a couple of weekends ago and on the way there and back I noticed I was getting over 1 bar of boost at barely half throttle again. Checking with Espritmon earlier in the week showed the MAP sensor maxing out at about 50% throttle. I'd previously tested the operation of the wastegate solenoid before I sorted the actuator setup, but clearly between then and me reinstalling it now its gone bad and got stuck bleeding the air off the actuator constantly, resulting in uncontrolled boost (up to a point) and this despite Espritmon showing the WGDC triggering. I tested the solenoid with a battery today and no signs of life from it now, so I've got a new one on order from the US. They're about £120+VAT from the usual suspects in the UK, if they have them in stock. Got one from the states for $64; at about half the price I'm prepared to wait the week or so it will take to be shipped here!

[Chefchen]

Thanks for your impression on the Nankangs. Since I'm not planning to drive my Esprit on the track, I'm still wondering if these tires are the right ones for me, since they are a kind of semi slick and therefore may be too "extrem" for the road!?

Concerning your idle problem - had the same behavior on mine. I put my TPS in isopropanol for an hour or so and reinstalled it - everything fine again and no idle problem any more since then (for over one year now). So may be you can do this with your removed TPS and have a workable spare part again 😃

[tomcattom]

Luckily I haven't thrown the old TPS away, so I'll give the IPA and see what it does @Chefchen.

New wastegate solenoid turned up today so been out and fitted it this evening and gone for a run in the evening sun.

 

I can't be totally sure the new solenoid has fully worked yet, the boost gauge decided to crap out on my while I was out for the run and I failed to take the laptop with me That said the boost did feel like it was being delivered in a more controlled manner than it did before. I'll go out for another run over the weekend and see what Espritmon makes of things now.

[tomcattom]

I've had a set of RC PL2-370 primary injectors waiting to be installed for a couple of months now.

 

Finally found the time to install them this afternoon, plus I'd been holding on until I could do a fuel pressure test before fitting the new injectors just as a reference point for before. Took me about 45 minutes all in to do the swap. Trickiest bit I found was getting the clips back onto the injectors to hold them into the fuel rail. There's not enough space to install the clips after fitting the new injectors, so I found I had to half fit the clip to the injector, push it into the fuel rail and then engage the retaining clip the remainder of the way. The remaining three went in like a piece of cake once I'd worked out how to fit the first one.

Out with the 25 year old Rochesters...

 

And in with the shiny new RCs

 

I've briefly started the car and couldn't really notice any discernible difference in the way the car ran, but then idling hasn't been a particular issue for me, it's more the flat spot low down in the rev range I'm hoping these will help resolve. Taking it out to a cars and coffee meet tomorrow so will run it properly then and see how it performs.

[Giniw]

(I am a bit late to the party, but don't forget to reset the ECU BLM)

Edited July 25, 2022 by Giniw

[tomcattom]

I hadn't reset the BLM, but I have done so today following the installation of the new IACV.

[tomcattom]

In the last few weeks several new components have been fitted to the engine in the pursuit of resolving recent stall on initial start from cold. You can follow the ongoing progress of that here:

 

After changing a few things, including the injectors, IACV, vacuum hoses and rear non-return valve, today I have fitted a new fuel pressure regulator and the first start has showed encouraging signs, if not convincing me that it's 100% cured, but hopefully a few more cold starts to build confidence will convince me its cured 🤞

[Giniw]

Have you checked the fuel pressure while the engine is idling?

I would be curious to see if the pressure is absolutely still, also how fast it reacts when revving the engine from idle, etc (to compare to a used one like mine)

[tomcattom]

When idling it seems to hold pretty steady on both the new and old regulator. I've not tried revving to see what it does then.

Sadly however, I didn't use the car for a couple of weeks and when I came to use it again last weekend the cold start stalling issue had returned I did have some issues with the new fuel pump not working when I first fitted it to the car and all this is now making me wonder if there is still a subtle problem with the pump being a bit "lazy". There's not much left that I can replace in regards to the starting side of things, so I'm just clutching at straws with that thought. Will try another pump during its winter lay-up and see if that has any effect.

[Giniw]

I may be late to the party for suggestions but maybe with espritmon you can check if it's running lean or rich just before it stalls? (lean=fuel starvation, rich=air starvation?)

[Jacques]

Just out of curiosity, take up the new pump and see if some funny little pieces of green mesh have found their way into the pump, or passing the strainer, making it "lazy".

I suspect that you left the old pump fuel limiter (the one that limits the pump "hits" - don't know what it is called).

Kind regards.

[tomcattom]

Not quite sure what you're referring to @Jacques. It was a brand new Sytec pump and strainer that came with it that went in and a brand new alloy tank. The only bit I reused was the metal cradle/hanger (or whatever you want to call it) that the pump sits in. Not sure what this green mesh you're referring to is, or where it might have come from.

The pump is coming out either way to try another one to see if that solves the problem; so I'll give it a thorough inspection. I haven't really got anything to lose by doing it during the winter layup while other work is taking place.

[tomcattom]

First piece of work on my winter programme has commenced today with a relatively straightforward job, fitting a clutch assist sprint. My wife is insured to drive the car and wants to drive it, but really struggles with the weight of the clutch pedal and that isn't helped by the fact we live in the middle of town so to get anywhere requires a fair amount of clutch use just to get out of town.

I'm aware of the reasons why they were removed from cars, but so far, having fitted it the pedal does seem a lot easier to modulate, but I've not actually driven the car with it yet to see if the "over centre" effect of it is overly pronounced. Worst case scenario, if I don't like it I can remove it.

The assist spring is actually quite nicely made, there are little needle bearings inside the spring caps at each end where it pivots on the pedal and pedal box at each end. Mine was a bit stiff to start with; it's probably been sat in a damp shed or garage for years before I bought it second hand. After a quick clean up and smear of grease they run quite freely now.

 

This is clutch pedal before I started. As is nearly always the case with this car, you start one job and discover another to do in the process. There is evidence of hydraulic fluid at the back of the pedal box around the clutch master pushrod opening - guess I'll be adding a new master cylinder to the to-do list this winter 🙄

 

And here it is all fitted. Not the easiest item to battle with to install, the spring is quite strong and needs to be pretty much fully compressed to install it. A couple of strong zip ties came in really handy as makshift spring compressors 😁

[Gibbie]

Brilliant - I’ve been looking for a clutch spring unit for some while and for much the same reason, but never managed to locate one!

Jennie, my wife, also struggles with the clutch pedal loading.

Keep us posted as to how you get on.

kind regards

Paul

[jonwat]

On 22/11/2022 at 13:46, tomcattom said:

having fitted it the pedal does seem a lot easier to modulate

I had the assist spring fitted to my S4s because of my dodgy knee & yes it does reduce the effort required by around 50% & I never found the over centre effect too pronounced. 

[tomcattom]

Not back in here again **sigh**

[tomcattom]

Well preventatively replacing the fuel pump when I changed the tanks last year has well and truly backfired on me because I've ended up having to change the pump again today 🙄

Throughout last summer I was chasing a cold starting issue and replaced numerous components and I thought I'd cracked it with the fitment of a new fuel pressure regulator, but not long after that it started misbehaving again to the point where it failed to prime, let alone start in the last couple of weeks so changing the FPR must have just been a brief fluke.

I'd always had a nagging feeling something wasn't right with the first replacement pump I bought from day one of fitting it when it wouldn't even prime. Over Christmas I had researched and bought an alternative pump to see if the other pump was indeed faulty. The new pump had a few differences to the last one I bought; it has an eccentric pickup (matching OE) and it also had a lower flow rate than the last pump, but still higher than OE. While researching the pumps the second time around I'd noted that the last pump I'd bought could potentially pull more current than the OE wiring is rated for, so in the interests of safety I picked one with a lower flow rate and therefore lower peak current draw.

The new old Sytec I fitted last year on the left with the new new Racetronix pump on the right.

 

Upon opening the package at the start of the year when the pump arrived I was greeted with a nice set of instructions (unlike the Sytec which had none in the box) with a big warning box that tells the user not to block the priming port on the bottom of the pump because it will result in "poor or no priming" and possible failure of the pump. It also goes as far as to advise cutting a relief hole in the rubber boot that goes on the bottom of the pump to ensure the priming hole isn't blocked. This immediately got me wondering if the Sytec pump had the same priming hole, but I couldn't see it from the photos I took at the time, but it would certainly explain my symptoms because I never cut any relief hole in the boot I used for that pump.

Here is said priming hole on the Sytec pump, having removed it from the car today. it was most definitely obstructed by the insulating boot supplied with the pump.

 

This is the new Racetronix pump with the boot fitted after cutting the necessary relief hole for the priming hole, which is just visible. Note how the fuel pickup is off centre as per OE too, unlike the Sytec, whcih was listed as compatible with the Esprit, I might add.

 

And here it is all reassembled in the cradle with what you can see of the relief cut.

 

After reassembling everything the pump primed on ignition on, it started after only three cranks from the starter and more importantly, it didn't stall at all

So after twelve months and two new pumps I think I have finally cracked my cold starting issue, and all because of a innocuous little hole in the bottom of the pump. Will check it again tomorrow to make sure the cold start today wasn't a fluke 🤞

[tomcattom]

Started perfectly from cold without a sign of a stall again today 😁