Heavy sttutering and stalling

[iimomar]

Upsss... Sorry Robou, you were right. I wrote that but still don't know why... perhaps my subconscious was thinking in the flames of a 480 on fire.

Anyway... the correct references and codes of the ECU's are the ones stated on my last post, Purple EZ210K and Brown LH2.2.

[doingitsideways]

Probably not helpful, but have you tried this?:

http://m.youtube.com/watch?feature=plpp&v=78b67l_yxUc#

Steve

[iimomar]

Well... I was thinking on something a bit more aggressive than this ...

[svenska axel]

could it no be ignition, distributor, leads plugs. could show up on heavy load boosting.

[iimomar]

Well guys… happy news at the end…

Tired of unsuccessful checks and seriously considering breaking the car… I decided to give him his last opportunity and took it to the garage. The mechanic told me that the problem was related with a faulty flywheel sensor, which stopped sending signal when the engine was under load (which also was my first stuff to check…) but when he replaced it,he realized that the behavior of the car was exactly the same (same as me…). After a long while and many headaches he found a peeled wire which was contacting the engine when it displaces due to the load. He didn’t give me more detail about which wire was… but I guess it should be one related the flywheel…

Anyway, 30 euros and problem solved!

[doingitsideways]

That's great news

Maybe he could have a look at my 460?!

Lol

Steve

[jamesy12345]

Happy ending good news matey

[iimomar]

Mostrar detalles

Well, I want to tell the end of the “heavy stuttering” history just with the hope that it can help someone with similar problem. As I said on previous posts, the mechanic identified a problem with a connector as the source of the problem. I thought that it should be the flywheel sensor connector, but when inspected the car at home, I notice that the faulty connector was the fuel injector one (The 6-pin one in which only 4 are used). The mechanic did a botched job, just to avoid the problem but he did not replaced the connector. So, I replaced with a new one, and after that… upss… only 3 cylinder were firing. After removing the inlet manifold I noticed that the isolating of the injector wires and their connector was in very very bad condition… nearly desintegrated... So I had to do new wires fitted with new connectors and problem solved.

As I read on old posts and I saw on the electric schemes, the wiring of the 4 injectors it's quite strange. And I cannot understand how each injector can be fired at the required time. Are the 4 injectors fired at the same time? I am wondering if a Volvo 480 electronic guru could give us a masterclass about how the firing of the injectors works...

[jamesy12345]

There are lots of 480 gurus on here. Unfortunately I am not one of them but I like to guess at things........from memory the injectors fire when the ECU allows them a path to earth via pin #13 (of the Jetronic ECU). Yes the wiring can be damaged by heat - I saw this on my parts car

[iimomar]

Correct Jamesy, the injectors are connected to 12V and to pin 13 on the ECU, the ECU fires the injector by grounding it through pin 13 (I guess...). But all the 4 injectors are connected to the same pin, so… how can they be fired at different times???

[jamesy12345]

ummm...

4. Applicability to others Volvo 400 series
According to Haynes handbook, various injection systems have been installed on Volvo 400 Series (440, 460 & 480) :
- B18E semi sequential injection: injectors being grouped 2 by 2 on ECU ports 20 & 21 … Flexitune II is not convenient in this case and Flexitune S with only 2 installed channels should be used in instead.
- B18F & B18FT: simultaneous system on ECU port 13
- B18 EP, B18FP, B16F, B18U, B20U et B20F: simultaneous system on ECU port 21

http://www.etanol.nu/forum/viewtopic.php?f=42&t=3321

Multiport fuel injectionMultiport fuel injection injects fuel into the intake ports just upstream of each cylinder's intake valve, rather than at a central point within an intake manifold. MPFI (or just MPI) systems can be sequential, in which injection is timed to coincide with each cylinder's intake stroke; batched, in which fuel is injected to the cylinders in groups, without precise synchronization to any particular cylinder's intake stroke; or simultaneous, in which fuel is injected at the same time to all the cylinders. The intake is only slightly wet, and typical fuel pressure runs between 40-60 psi.

Many modern EFI systems utilize sequential MPFI; however, in newer gasoline engines, direct injection systems are beginning to replace sequential ones.

http://en.wikipedia.org/wiki/Fuel_injection

and for loads of detail on testing.....

http://www.volvoclub.org.uk/tech/servic ... eforms.pdf