Technical Random starting problems after cambelt change

[Voko]

Hi All,

A bit of an odd issue, I changed the cambelt using the guide and confident everything is set up ok, went for a drive everything ran beautifully. However, sometimes when I start the car it has to crank for ages (10s of seconds) before it starts, but sometimes it starts first pull. Once it does start it runs perfect idle and on the road. I’m guessing I’ve disturbed something, or having the battery disconnected a long time has done something. Could be a coincidence? Anyone have any thoughts about what could randomly effect starting but nothing else, it can happen hot or cold I can hear the fuel pump prime every time and the ‘key’ symbol goes out on the dash

All done an ECU scan etc no errors showing

Cheers

Mike

 

[tjr]

Hi Mike,
Glad to hear all went well with the cam belt swap. Just wanted to offer my good luck wishes!

Lacking the competence and having half-sorted cold-cold start issues on the b-95 (see link below), I'll for your sake abstain from any guessing(!). For the b-95 I'll continue disconnecting and cleaning sensor and ground connections. If the problem(s) persists I'll, thanks to @Ilkka, start investigating the Lambda sensor, MAF, and individual fuel injector function.

Good luck in the sleuthing and hoping you'll share your findings/ruling-outs for forum-hive-knowledge-bank building,
tjr

Fuel pump(?) advice sought... | FIAT Barchetta

The b-95 is now 29 years old, so I suppose all parts have the right to give up... Symptoms: The b-95 has always been eager to start during the two years I've known it, but this season, it is in need of "priming", ie activating the pump 2-3 times with the key (back and forth between OFF and...

www.fiatforum.com

 

[Voko]

Thanks…nothing found as yet, I might try swapping out the crank sensor as they are cheap….one thing that is cheap

 

[Voko]

Changed the crank sensor made no difference. Cleaned every relay, fuse and connector I could find in the engine bay, no difference. I think the next stage is to double check I’ve got the timing right, still not convinced it would give these random symptoms though, unless it’s very sensitive to differences in crank and cam sensor output

 

[tjr]

Thanks for the update, sorry about the dead-end.

(The b-95 has been garaged since last fall, this evening I discovered flats on both front tires... On a positive note it started right up(?!).)

 

[tjr]

Changed the crank sensor made no difference. Cleaned every relay, fuse and connector I could find in the engine bay, no difference. I think the next stage is to double check I’ve got the timing right, still not convinced it would give these random symptoms though, unless it’s very sensitive to differences in crank and cam sensor output

The cam position sensor is/was alright? I damaged it, but I had both cam’s out.

 

[Voko]

I can only assume so, didn’t do anything that could damage it

 

[s130]

Did you use the proper timing tools? i.e. crank and cam lobe locks?

Some engines don't really start that well if the static timing is to far advanced but once up and running some love the extra advance which can be misleading.

 

[Voko]

I think you might be right… I’m checking now, I’ve got the right camshaft locking tools, and improvising locking the crank. When I did it the first time round it seemed too far retarded (on the flywheel marks), and I brought it forward, so perhaps that was a mistake

 

[Voko]

I’ve now had a minor disaster and stripped one of the threads in a cam shaft bearing cap - help!

 

[tjr]

Tough deal, but not uncommon...

The two options I know of are:
Helicoil - check that it'll hold the required torque.
Drill and tap - will require a new larger diameter bolt that may affect the bearing cap (may require drilling).

I'll let somebody with more experience weigh in on the pros/cons and possibly offer additional alternatives!

 

[Voko]

Thanks, yeh would appreciate advice. The original bolts are 7mm, the cap will take a 8mm bolt without drilling. Slight complication is a ‘dowel’ that sits proud for location of the cap. That has a 9mm outer diameter and 7mm internal. The torque is only 15nm, so I don’t think needs to be overly strong. I’ve got work colleagues who are excellent as this kind of stuff so I’ll run it by them

 

[Voko]

Thanks, yeh would appreciate advice. The original bolts are 7mm, the cap will take a 8mm bolt without drilling. Slight complication is a ‘dowel’ that sits proud for location of the cap. That has a 9mm outer diameter and 7mm internal. The torque is only 15nm, so I don’t think needs to be overly strong. I’ve got work colleagues who are excellent as this kind of stuff so I’ll run it by them

Dowel out, 7mm Helicoil in, new dowel in, all looks good, that’s a relief, should be stronger than original now

 

[s130]

Dowel out, 7mm Helicoil in, new dowel in, all looks good, that’s a relief, should be stronger than original now

Not fun when these things happen.

Hopefully now you can reset the timing OK and she'll start OK.

What I don't like about doing this job on the 'B' is that the rocker box gasket is terrible in getting a good seal as it goes round so many twists and up / over /down again leaking at the camshaft pulley end is a common and re-occurring issue.

 

[Voko]

Car back together, I had to move the pulleys to get the timing spot on. The good news, still runs and drives perfectly. The bad news doesn’t start about 40% of the time….grrrr

 

[s130]

Just a thought .....

Are you certain that the immobilise light has gone out. Our 2005 B has a habit of not starting on 1st attempt. You often get in, ignition on and to start and it just cranks. Ignition off, pause, on and wait to see if the immobiliser light clears down. Sometime it take a couple of goes before all is cleared.

Annoying but it has been doing this for years and years and years.

 

[Voko]

Thank yeh, it goes out every time. I’m suspicious about these cam setting tools…before I changed everything the crank was about 5 degrees retarded when the can was locked. I ‘corrected’ this, but it seems odd I had to move both pulleys to achieve it. All else fails I’ll set it back, to at least rule it out as an issue

 

[s130]

Are you setting TDC by using the inspection hole on top of the gearbox bell housing? This is the most accurate way EXCEPT for levelling all pistons to the same depth and going back 180 degrees.

Also there is the possibility that the TDC sensor is not in the correct position. We had this on our Tempra 1.8ie where the sensor bracket, mounted with sheer bolts was not in the correct position.

 

[Voko]

Yes, I’m checking through the inspection hole. It was definitely a long way out when I started. I’m not sure there is a TDC sensor on a bracket, but I have replaced the crank position sensor at the rear of the block in an attempt to fix it. I’ll get back on it on Friday, so it won’t take me long to establish whether it is timing related (by setting it back to how it was) or something else.

Thanks!

 

[Voko]

Yes, I’m checking through the inspection hole. It was definitely a long way out when I started. I’m not sure there is a TDC sensor on a bracket, but I have replaced the crank position sensor at the rear of the block in an attempt to fix it. I’ll get back on it on Friday, so it won’t take me long to establish whether it is timing related (by setting it back to how it was) or something else.

Thanks!

The cam position sensor is/was alright? I damaged it, but I had both cam’s out.

It’s interesting the car won’t start at all when I disconnect that sensor, but once running will run without it. I sure I’ve been well clear of it but definitely a thing to check when I’ve got the covers off again