Pagoda SL Group

W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: mauro12 on September 24, 2020, 16:28:48

Title: New fuel injectors failed
Post by: mauro12 on September 24, 2020, 16:28:48
Hello guys , I’m quite disappointed, I bought last week 6 brand new fuel injectors and the car is running like a crap or even worst. No power, no acceleration , huge smoke and not stable idle . Tomorrow I will put back the old injectors and I will see if this is the problem . If yes I think I’ve been ripped of with fake bosch injectors . I don’t have any other words. How is possible that the car is running worst with new injectors ?
Title: Re: New fuel injectors failed
Post by: Jonny B on September 24, 2020, 17:30:09
I have purchased new injectors before, and was surprised to find that one of them did not function properly. Unfortunately a new part being bad is not unheard of. All six however is, unless as you say they are fakes.

Are you able to have the injectors tested to see if they have a clean spray pattern and open at the proper pressure?
Title: Re: New fuel injectors failed
Post by: mauro12 on September 24, 2020, 17:35:30
Maybe some of them are working some not. The fact is that after we put the new injectors , that car run terribly. The engine was shaking with huge smoke and no acceleration. Was impossible to pass 3000rpm. We didn’t touch the pump, so I assume that the problem are the injectors . I will pack and send back and hopefully have a new set back once again. I think is enough that 3 injectors out of 6 do not work and the result is a bad bad running engine .
Title: Re: New fuel injectors failed
Post by: Pawel66 on September 24, 2020, 21:37:23
No surprise, actually, had a very similar issue.

If you have a tester (e.g. Kent style) it is sometimes possible to liven them up. This tester comes handy to check them, make a film for claim, etc.
Title: Re: New fuel injectors failed
Post by: mauro12 on September 24, 2020, 21:51:28
How is possible that a set of new injectors do not work? Are they fake?
Title: Re: New fuel injectors failed
Post by: Pawel66 on September 24, 2020, 22:03:32
The whole set?

I had like 1 in 3 not working. If you say the whole set, I am starting to be suspicious.... Could be certain lot was produced with fault.. no idea. Or something else went wrong. Maybe if the old ones were leaking, someone leaned mixture and it is too lean now... I am probably writing nonsense...

Do you have a way to test them? Have you tried to fit one to the line outside of inlet to see it spraying fuel?
Title: Re: New fuel injectors failed
Post by: mauro12 on September 24, 2020, 22:11:05
When I put the new set of injectors , the car run worst and worst than before. I don’t know if 1 or 2 or 3 injectors are working or not. For sure some of them aren’t . Tomorrow I will put back the old injectors and if the car come back to normal it means that Injectors are the problem .
Title: Re: New fuel injectors failed
Post by: mrfatboy on September 24, 2020, 22:24:22
I agree with Pawel that your pump might be too lean now with good injectors. Someone might have tried to compensate for the old leaky injectors or even a stuck WRD.

You need to check everything.
Title: Re: New fuel injectors failed
Post by: mauro12 on September 25, 2020, 18:19:54
Hi guys, the car came back normal as it was with the original 53 years old injectors . I cannot find an answer. Could be some injection pump issue? Or maybe the new injectors didn’t work, maybe some of them. Anyway, I gave back this injectors and I will wait a new set. This experience was frustrating. I Hadn’t  thought that a car with new injectors would have been worst than before .
Title: Re: New fuel injectors failed
Post by: Pawel66 on September 25, 2020, 21:17:02
mauro, the Kent style injector tester costs peanuts and may come handy. In my country I could find only diesel ones, so I bought one and replaced the gauge.

https://tooles.pl/tester-probnik-wtryskiwaczy-600-bar-adaptery-geko-tes17?gclid=Cj0KCQjwqrb7BRDlARIsACwGad7sdJXcAkKnRo6D45BCFAL5RjxS6Amwfk2vHjTFzGIp2vxzOm0GPkMaAoa9EALw_wcB
Title: Re: New fuel injectors failed
Post by: mauro12 on September 26, 2020, 11:13:45
I have seen many videos with Kent regarding the bench test of injectors. My question is: is there any possibility that old fuel injectors Works better than new one? I’m pretty sure 1 or 2 of my new one didnt work well.
I also started to think that maybe new injectors spray too much fuel that the old one, maybe is a silly explanation but I don’t have any others.
I sent them back and I wait to receive a new set. What is the first improvement with new injectors ? Better acceleration and fuel economy I guess. I didn’t have any of those improvements.
If someone has some other explanation would be great. Maybe Benz dr has some.
Title: Re: New fuel injectors failed
Post by: mdsalemi on September 26, 2020, 19:24:16
...in my country I could find only diesel ones, so I bought one and replaced the gauge.

Pawel, I think that is exactly what Kent Bergsma did in his video; use a diesel injector tester and replaced the pressure gauge.

Our member here Jim Villers, the consummate tinkerer (that'a compliment!) put one together and demonstrated its use at PUB in Charlottesville in 2017. Not only does it "test" the injectors, but it can help "restore" one too. A number of injector sets were done for folks at PUB. There were a few that could not be brought back to good working order but a number of them could.

I think it can be put together (the tester) pretty inexpensively.
Title: Re: New fuel injectors failed
Post by: Pawel66 on September 26, 2020, 20:15:02
mauro, to the best of my knowledge, old injectors usually leak and are not able to build pressure to produce spray. That causes rich condition. If someone leaned the car to compensate for leaking injectors, with new injectors you will have lean condition, the car will not work.

Most likely you will get a new set of injectors form the same production lot as those you had - if it was wrong, it will be wrong. To determine if the injector is ok or not, you need a tester or you need to fit it on the line without fitting it to the intake manifold, crank the engine and see if it is spraying fuel. It will not tell you, however, the opening pressure.
Title: Re: New fuel injectors failed
Post by: stickandrudderman on September 27, 2020, 09:39:56
You should not expect to change any component that influences combustion and not check the basics like timing and mixture afterwards.
For example: I've seen plenty of cars that have been stuck on cold start for years; fix the cold start and suddenly the engine runs terribly when hot. Customer complains, "It wasn't like that when I brought it in....."

That said, it is not unheard of for a new part to be defective and the only way to know is (in this case) bench test the injectors.
Title: Re: New fuel injectors failed
Post by: mauro12 on September 27, 2020, 20:40:50
When I put the new injectors , i did everything I could to change and adapt the mixture but the car wasn’t happy at all.
I thought and I still believe that new injectors must work better than 53 years old injectors.
Having said that, I’m sure is enought that one of them is defective and the result is an undrivable mess.
Title: Re: New fuel injectors failed
Post by: mauro12 on November 04, 2020, 08:28:44
Hi guys, just a quick update about my injectors . I have been totally refunded from mbclassic.de because they were defective from the factory . It means that even new bosch injectors can fail right out of the new box. Having said that I cleaned and tested my old r1 and I think they are better quality than the r2.
Title: Re: New fuel injectors failed
Post by: Pawel66 on November 04, 2020, 12:28:48
Good you got to conclusion and good you were refunded.

Blood, sweat and tears, however, will not be refunded... also time lost.

As I wrote before, I also spotted faulty new injectors, but not so many in a lot.
Title: Re: New fuel injectors failed
Post by: mauro12 on November 05, 2020, 17:31:02
They didn’t tell me what was the problem, they just refunded me. But really was a nightmare . The car was smoking like a chimney . I’m sure they had a pressure problem .
Title: Re: New fuel injectors failed
Post by: dirkbalter on November 05, 2020, 18:11:49
Wow, I just bought a set of injectors for future use. Bases on what you guys experienced, I guess I should check them be fore I put them away.
Title: Re: New fuel injectors failed
Post by: 114015 on November 05, 2020, 18:20:50

Yes..., Mauro, Dirk,

That's the truth.
The new injectors look like new and originals
but they are nowadys made 'anywhere' in the World
and also of lousy quality.  :o
You always have to check them first before use.  ;)

Used 8 new injectors and only 6 good usable ones were among them (by their spray pattern). :-[ ;)


Keep smiling,


Achim
Title: Re: New fuel injectors failed
Post by: dirkbalter on November 08, 2020, 03:17:16
Achim, Mauro
Just as a FYI. I tested the new injectors and am relieved to report that they seem to be good. One of them wouldn't hold any pressure initially. I had to really "pump it hard" a few times before (I guess) it seated properly and holds pressure and shows a nice spray pattern. 

Title: Re: New fuel injectors failed
Post by: lurtch on November 08, 2020, 04:47:42
Hi Mauro,

a post I made last year might help with your dilemma:

https://www.sl113.org/forums/index.php?topic=30314.msg219507#msg219507
Title: Re: New fuel injectors failed
Post by: perry113 on November 19, 2020, 14:46:32
Just trying to clarify issues with new fuel injectors.
Has this been proven?
I am in the market to buy at least 1 new (a good known set) as I have 2 230SL's.

It would be alarming to know that new ones are a crap shoot.
Title: Re: New fuel injectors failed
Post by: mauro12 on November 20, 2020, 22:29:12
I bought new injectors from
Mbclassic.de , I installed and right after the car was running very bad . There was no acceleration and was smoking incredibly . I put the old one and the car run like it used to
Be. For this reason I gave back the injectors to them and they sent to bosch . After one month I’ve been refunded and I have been told the the injectors were defective . They didn’t tell me what was the problem but only that there were not ok. I have to thank  mbclassic for their help and cooperation.
Having said that I’m not telling that all
New injectors are crap but only that maybe I have been unlucky . My own thought is that maybe old injectors were made by bosch and maybe these new ones  are made on their behalf but I’m just guessing .
I decided to clean my old one and test. The results is great , they are working fine with no issues .
Title: Re: New fuel injectors failed
Post by: Pastarnac on May 16, 2022, 00:21:41
Just to add more to this topic…

I also bought a set of injectors with the idea to improve the performance of my 280sl.

Injectors were in individual  ones with some small holograms and individual serial numbers on the boxes and stamped on the injectors .

Bottom line I ended up with a rough ride, strong vibrations like it was running in less cylinders. The idle was varying with occasional drop.

Long story short it turned out one of them was leaking ; it was not even  holding gas.

I find out after I put together a primitive but effective enough pump to test the spray pattern.

I do not know what to say. They were marked as made in Genrmany and I got them from Rock Auto.
I plan to return them all. What kind of confidence I should have on the rest of them?
Title: Re: New fuel injectors failed
Post by: Kevkeller on May 16, 2022, 21:27:37
I bought a diesel injector tester on eBay from India a few years ago to test my injectors. I also bought a new set of injectors and I think 3 had terrible spray patterns. I exchanged them but never tested the new ones.

There is a difference between a diesel spray pattern and a gasoline pattern I imagine though probably not that much difference.

Pawell I think a leaky injector would cause a lean burn because the fuel would not vaporize as well thus not burn as well. Now if the injectors leaked and the engine was burning lean the owner would enrich the mixture to compensate. When good injectors are put in all of a sudden the engine would be running super rich.

The testers sell for less than $100 on eBay. I might buy another to test my damn brake calipers which are still causing me problems with rebuild kits.
Title: Re: New fuel injectors failed
Post by: mauro12 on May 21, 2022, 09:58:10
In my case I have been refunded for the defective injectors. But I have been told that the r2 injectors are lower quality than the r1.
Title: Re: New fuel injectors failed
Post by: Kevkeller on May 21, 2022, 20:58:20
Interesting.  I wonder what the difference between the R1 and R2 is other than quality.  I’ll have to check which ones mine are.
Title: Re: New fuel injectors failed
Post by: mauro12 on May 21, 2022, 21:05:03
The r1 injectors are nla unfortunately. Some people say that the r2 are not as good as the r1 . After having spent 800€ for a new set of r2 the result was horrible . Probably they were defective , for this reason they gave me money back , but I don’t have the courage anymore to try and buy a new set again . My r1 are good but they suffer from a little low opening pressure . This condition affect the performance but not too much .
Title: Re: New fuel injectors failed
Post by: MarkCan on June 04, 2022, 17:58:16
The r1 injectors are nla unfortunately. Some people say that the r2 are not as good as the r1 .

I had a chance to test both. I would agree that r1’s have better/wider spray pattern. That’s not to say that gen. 2 are bad. Just different. We shall be happy that they are still available.
Anyway, when testing I found that not all suggested test fluids perform equally well. Diesel for example “failed” most of the injectors on 2nd and 3rd round yet on the initial test the spray and pattern where somewhat ok. There was a specific test oil that did not score well in my book either. I had best success with diesel purge. Probably because of it’s cleaning quality’s. I was able to reproduce the results with gasoline every time after.
Mind you, those tests had to be performed outside.
Title: Re: New fuel injectors failed
Post by: Kevkeller on June 04, 2022, 22:07:13
Good to know regarding the different fluids. Thank you for sharing.