Starting and timing issue. Solved? Not quite!

[Fetnas]

So a bit of back story to start with. The car has been used very little for the past too many years due to other life things and such. About a month ago, I completed upgrading the brake booster and brake lines in order to get the car safe to use as my daily driver. I also changed the water pump, as the old pump's impeller was badly corroded, and renewed the timing belt. Apart from chasing down a couple of leaks in the cooling system it all went well. The past month has seen some extreme weather conditions from mid 30 degrees to a couple of day s of 50+mm of rains! That's late spring / early summer in Melbourne for you!

In the past, the car has almost always started very quickly, as in starting within a second. That seem pretty good to me. But a couple of weeks back, the car coughed when it normally would have started, and died. It then took a lot of encouragement to get it going again, several long cranking sessions. When it finally started it wasn't running on all cylinders, but it cam good after a few minutes. The next time it started, it was back to normal. Then the hard starting happened again a few days later, or it would start but not on all cylinders, but still start properly most of the time. When heading out to leave work last Thursday, when it was raining heavily, typical, the car coughed on first start attempt, spluttered a bit and then died. I cranked it a lot, tried to start it with a little throttle and then with full throttle to engage flood mode just in case I'd flooded it, not luck. When there was a lul in the weather, I pulled out the tool kit to check the plugs. All 4 were dry with no sign of any fuel, not even a whiff, none at the exhaust end either! I had to catch a train home in the heavy rain leaving the elan at work, annoying.

The next day at work, i tried to start it again. Same result, an initial cough then nothing regardless of the cranking. It's a good thing the battery seems to be a strong one, despite being over 10 years old! So I arranged to have it tilt tray trucked back home. My dad received the car of the truck and though he'd have a go at starting it, and of course, it did. Grr! Clearly there is an intermittent problem that needs fixing.

Now to go through the list of things that can be eliminated. Yes, the fuel pump runs for 2 seconds when the ignition is turned on and the fuel tank is basically full. The plugs, leads and coil packs are relatively fresh as they've probably only done 10,000 miles max. With the ignition on, opening the throttle body makes the injectors click, so they're getting power and the Ecu is controlling them.

Researching the workshop manuals, I'd come to the conclusion that the CAS was probably faulty as it is a common point for the control of the spark and the fuel timing. Thankfully I'd bought one of the replacement CAS units from aftersales a while ago so this was the time for the swap. Before disconnection the battery for the CAS swap, I checked the error codes and was presented with code 33, MAP sensor out of range, but no CAS errors. So proceeded with the CAS work, put it back together, reconnected the battery and turned the key. Now I knew timing wouldn't be correct but it again took quite a bit of effort to start, but once going, it ran, not great, but OK. Let it get up to temp, pulled out the brand new timing light only to find it was dead, I didn't need that or the time wasting trip to get it replaced.

So back with another timing light, which thankfully worked, got the car started a bit reluctantly, it would run then the idle would drop down and it would die. Got it running consistently and back up to temp, put it into service mode, brought the revs slowly up to 2000 and back down to zero throttle. Checked the timing and it was quite a way off and bouncing around by 3 to 4 degrees, is that normal? Also, the idle was quite high at this point, around 1400, is that normal in service mode? So with the timing set closer to 16 degrees than it was, took it out of service mode, the revs dropped the car kept running, but not quite right. Turned it off and started it again, but still having difficulty getting it going, it seems to need about 25% throttle to get it to start then after a few seconds of revving, it would let me release the throttle without stalling.

I'm a bit frustrated and puzzled as to what's going on. As another trouble shooting check, the timing light was tested on all plug leads to make sure they were all firing, which they were, but the strange observation was that plug 1 and 3 were firing at about half the frequency of 2 and 4, which isn't making much sense to me as I know the coil pairs are 1-4 and 2-3. Does anyone know if that's normal or is it a sign the coil base plate is faulty? I'm suspecting the base plate is going out of spec as it's the first point the timing signal goes to and the fact that the engine dies when the revs drop also points to the base plate taht looks after timing below 800 RPM. Does that make sense to anyone? Are there replacements available? I know of 2 other cars in my family that have also had ignition controller modules break down and go intermittent so I know it's an electrically stressed unit.

Is there anything I'm over looking? I'll continue to read through the manuals to try to figure out what's wrong, but any tips, advice or suggestions will be very welcome as I've almost run out of ideas.

If you read this far, thanks for getting though a post that ended up longer than expected.

[lotustonybassplayer]

Give Brit-car-nut ( John ) a try, he had the modules a few years ago as I bought one. He might still have some left. Ps just a thought are all the vacuum lines intact

[clemo]

just so you know you are not being ignored by the lack of answers > i have read it but cant add anything . Will have a think whilst putting christmas decorations up .

[alan e]

You said that the plugs when removed are dry and no smell of fuel so I would be looking at the fuel side and not the spark and timing side it may be injector problem I don't think if they click means they are working but I may be wrong how to test them is in WikiLEC good luck hope you find the problem soon and its a easy fix.

[lotustonybassplayer]

Just another thought did you disturb any earth straps whilst you did your recent work on the car ?

[Fetnas]

Hi Lotustonybassplayer,

I don't think I disturbed any grounding points whilst doing the recent work, certainly not intentionally. That said, it's an easy one to check and can't hurt to clean them up anyway. I'll clean all the earths then at least I'll know that there is a solid electrical connection to all points. I have seen that Brit-Car-Nut had sourced some Ignition control modules. He still had some available midway through this year apparently. I've sent him a PM and left a message in the 'For Sale' section. Hopefully he gets in contact and is able to help me out. I'm pretty sure there are no vaccume leaks, as when it was running well, the idle speed was stable, but again, another straight forward this to check.

Hi Alan,

As far as I can tell, the only way that all the injectors would not fire is if power wan't getting to them or the ecu wasn't getting a timing signal to fire them, which I why I suspected the CAS. But now that I've found the spark frequency difference which matches up with the injector paring, I'm less confident of my earlier diagnosis. I guess I'll have to check the injector coils resistance to rule out another possibility, but the intermittent nature does make this sort of error hard to correctly diagnose.

Thanks for the advice so far, I'm sure it'll get sorted, but it'll probably take a while and cause a bit of cursing before I get to the bottom of my problem.

[Simon_P]

Also, the idle was quite high at this point, around 1400, is that normal in service mode?

No 1400 is not normal. The idle should be 950, indicating that there may be a vacuum leak.
First check for vacuum leaks particularly the Map sensor pipework. The takeoff is on the O/S end of the plenum and is a plastic fitting that is easy to break. Don't forget all of the pipes at the back of the engine which are easily disconnected when you change the oil filter.


While you are at it check the throttle cable slack.

Once you are certain there are no vacuum leaks put the car in service mode then check and adjust the idle.

[Brit-Car-Nut]

Hi Lotustonybassplayer,
I have seen that Brit-Car-Nut had sourced some Ignition control modules. He still had some available midway through this year apparently. I've sent him a PM and left a message in the 'For Sale' section. Hopefully he gets in contact and is able to help me out.

I sent a PM that seems to have disappeared (so I re-sent it just now), as well as answered your post in the For Sale section.

[lotusflasherman]

I agree with Simon. particularly about MAP Sensor - you said "was presented with code 33, MAP sensor out of range" but then went on to change the CAS but make no further comment about the MAP sensor..

Just for info - I've owned 3 SE's, I put 120k miles on first in 4 years, and about 30k on next two, and all of them usually started quickly, so quick you don't really hear it cranking, BUT all of them, once in the proverbial blue moon, would crank a bit longer and cough, pop up a CEL, and then fire up 'running lumpy'. It only ever happened at home on a cold engine, usually after a period of non-use. I found turning engine off and restarting usually solved it but once or twice I've driven a few hundred yards before the "turn off & restart" sorted it. Was usually in a hurry to go out and and each time I thought 'must see what error code is' but never usually got round to it,though I did try once and couldn't find anything by 'paperclip method'. Elanscan would probably be more enlightening but hasn't happened for a long time - maybe because I'm using it regularly.

[Rambo]

I agree with Simon. particularly about MAP Sensor - you said "was presented with code 33, MAP sensor out of range" but then went on to change the CAS but make no further comment about the MAP sensor..

I also find that very odd. After identifying a possible MAP sensor error code you go down the route of changing the CAS but without any previous history on CAS error codes

[Simon_P]

Read in order it makes sense.

Rebuild CAS which was probably worth doing anyway. Disconnect battery code dissappears.

It could be just be a one off cause by something else.

[Fetnas]

Regarding the MAP sensor, I did check the vac line to the sensor. I had the pipe pop off early on in my owner ship because someone had used clear vinyl pipe to connect to the plastic fitting at the end of the plenum. When the engine bay got hot, the vinyl softened, turbo spooled up, pressure went positive and the car started bucking like a crazy thing. I did do a visual inspection of the MAP plumbing but couldn't see any obvious problems. I suspect the error code was logged as the car was stalling. This error code hasn't returned with the car running long enough to get up to temp and do the timing, so I suspect it's OK, but I might disconnect the pipes and check them more closely. I have had experience with other GM ECU systems of this era throwing erroneous error codes, so I take the codes as a guide, but not an absolute.

The thing I need to investigate more closely now will be the service mode idle speed, it didn't seem right to me for it to be as high as it was for such a critical procedure. I'm starting to think that the vac reservoir for the HVAC in the left wheel arch may have been disturbed when working on the brakes, the connections at the back of the throttle body all seem fine.

I replaced the CAS as it's a know failure point and I had the replacement part which I had intended to replace for a long time. Seemed like the right starting point in the process of elimination.

Thanks for the advice so far. I'm looking forward to getting her back on the road as quickly as practical as the Elan experiance is making the Astra I'm back to driving feel very underpowered.

[Rambo]

Fetnas - in all the time I have owned Elan's (+14 years) and been on the forum I have only ever heard of 2-3 CAS replacements And, in one of those cases, someone also had a new spare lying around so they could eliminate that as a suspect

I have heard of a few replacement Hall Effect Sensors (HES) going but the majority of LEC owners who bought these at under £20 via the Lotus after sales offers still have them in an unopened bag. Myself included

Hopefully you will bottom this problem soon and can put the Astra back out to pasture

PS Incidentally, that service mode idle speed is way too high at 1400 rpm but I think that someone has pointed this out already ? From memory it's 950 rpm in both service and normal mode

[Rambo]

Was typing my reply and the site went down (error 404) so couldn't check, but now its back up, I see it was Simon who mentioned about the RPM

[Fetnas]

A quick update.

I've acquired a cheap hand vacuum pump and tested all the ancillary vacuum lines coming out of the intake plenum. A couple of the hoses had split where they attached. I cut off the split sections and pulled a vacuum on all the lines. The only one showing any sign of a leak was the line to the ventilation control in the cabin, but it was only a tiny leak, so unlikely to be an issue.

So it doesn't look like I have a vacuum leak issue, at least not on the ancillaries. Is there anywhere else I should check? I'm thinking I should clean out the IAC valve as i know these can get gunked up which affects idling. I guess I'l also have to adjust the idle screw on top of the throttle body to get the car idling at the correct level in service mode.

A replacement ICM has arrived thanks to Brit Car Nut which I'll fit soon, and I also have a set of replacement injectors if nothing else helps. I'll have to redo the base timing and idle before I know if I've fixed the problem, but I'm hope full I'm on the right track.

[Fetnas]

So the new ICM was installed which definitely improved starting, however, there were still idling issues with the car stalling a couple of times just after starting.

Once the car was up to temperature and put into service mode, the idle speed was once again high at which point I adjusted the idle screw on top of the throttle body which turned out to be about 4 turns too far out! Once the idle was set, the timing was fine tuned, it was only out by about 2 degrees, and is now rock solid. With the old ICM and CAS, the timing mark jumped around quite a bit.

So basically the ECU had run out of room to adjust the idle speed with the IAC valve which made starting difficult when the weather conditions weren't favorable.

My main intentions are to make the car as reliable as possible, so replacing old components with new, even if they haven't yet failed, is all OK by me.

I think I'll use a small dab of silicon on the idle screw to stop it from vibrating loose again. As a reference, the distance from the top of the idle screw to the top of the sleeve it is mounted in is 9.76mm for my car. If it ever moves again, I'll know where it needs to be set.

Once again, thanks for the advice on this, greatly appreciated.

[Rambo]

Glad you're sorted Fetnas

A blob of mastic is a good idea to prevent the idle adjustment screw moving of its own accord. However one of our LEC members (RayD) also had an idle adjustment screw problem. His solution was a bit more sophisticated due to his engineering background. It involved a tapwasher and a small screw and is a very neat and unobtrusive fix

See here .......... http://wikilec.com/view/Tickover

[Danevansgolf]

Excuse my idiotic brain. But what is and where is the icm (ignition control module) located. Cheers

[Brit-Car-Nut]

Excuse my idiotic brain. But what is and where is the icm (ignition control module) located. Cheers

The ICM is the base of the coil pack.

The two coils connect to it and the 3 harnesses connect to the ECM to generate spark and also return data to the ECM.

ICM.JPG

ICM2.jpg

[Fetnas]

Well it looks like I have more problems to sort out, primarily head gasket related!

I have had difficult bleeding the coolant system in the past, but when i recent replaced the timing belt and water pump, I did bleed the system completely and fill the header tank to the correct level. But now after a couple of drives, there are bubbles behind the thermostat and the level in the header tank has gone up significantly! I suspect this has been a problem for some time but has gotten worse when I was driving the car as my daily! Looks like i have a blown gasket between a cylinder and the water jacket, kind of explains why I was having such difficulty getting the coolant system water tight, what with compression gasses pressurising the coolant!

The car is still not starting as well as it should, but on the last shake down drive I did, it was running really well, in fact it was pulling better than it ever has before. I reckon that was thanks to the timing now being correct and rock solid. I got home, parked the car and turned it off. Went to start it again about 45 mins later and it was very unhappy, idle all over the place, almost stalling, back firing, and not responding to throttle inputs! I think I've managed to blow the weakened gasket between 2 cylinders as well. Time to run a compression test, possibly a leak down test and put the coolant system pressure tester on it with the plugs out, pressurise the system and stick a boroscope in the cylinders to see if I can spot the coolant leak.

I think this is the car getting revenge on me for not driving it enough over the last several years!

To be continued in the engine section of the forum!