Professional Cleaning Of CIS-E Injectors - PeachParts Mercedes-Benz Forum

Mike Murrell · #1 03-01-2006, 12:31 PM

Vehicle description further down in signature.

Last spring I added a can of BG-44K to a near empty gas tank and refilled with 93 octane fuel. Car ran ok for about 1/2 a tank then starting intermittently missing on the road. I suspected the BG-44K was breaking things loose and clogging the injectors. A few tanks full later, the problem cleared itself up. I never believed this single can of BG-44K got the system cleaned up.

A few nights ago I added a 16z. can of Berryman's B-12 Chemtool to a near empty tank, then refilled with 93 octane Shell. Car ran OK for the first 60 miles.

I stopped off to run an errand on the way home last night. Started car 15 mins. later - there was heat soak of course and about 2-3 miles later, car started missing intermittently on the highway. This happened just a few times, then cleared up for the remaining 15 mi. journey home.

Parked in driveway, ran a few errands, came back and started car. It died. Restarted OK and got it in the garage. Shut it off, then tried to restart without success - engine just cranked rapidly. I let it cool off for 5-10 min and got it to start, but the idle was erratic, bouncing up and down, then finally stalling. After a 2 hr. cool off, the car started w/o stalling and idle was fairly stable, though certainly not smooth.

This morning I started the car and it idled up to around 1000-1200 rpm like it always does and eventually settled down to around 600-700 rpm.

Last year when I used the BG-44K, I experienced most of my problems with a WARM motor as I did last night. I'm fairly convinced that both the 44K and B-12 caused this problem as no other work had/has been done and the car was running failry well before hand in both cases prior to adding the snake oil to the gas tank.

I'll likely have to run a couple of tanks of fuel through before this clears up and once that's happened, I'll go ahead and change fuel filter and any tank screens that may be installed.

I promised myself last night that I am finally once and for all DONE with fuel system products and will eventually pull the injectors and have them professionally cleaned.

I have had little success with garages in my area that supposedly specialize in an sort of MB work.

Could anyone point me at a repair facility that I could ship my injectors to for professional cleaning?. I believe it's going to take a measure this serious to reinstate the correct spray pattern/pressure.

Thanks for your time.

#2 03-01-2006, 12:37 PM

Mike,

I don't get it, what was the problem with the car in the first place? If the current difficulties were caused by the additive and DO clear up in a few tanks, how do you know the injectors need to be cleaned?

At the very least, why not do a spray test before sending them off? That will at least confirm that is a problem.

cheers,
dan r.

Mike Murrell · #3 03-01-2006, 12:54 PM

Dan:

Last year I performed what some would call an ign. system maint. tune-up.

Plugs, wires, dist. cap; rotor(all OEM) were replaced. Before and after this service, the car exhibited a slightly rough idle when cold. This was a new situation at the time - car had always idled smoothly when both cold and hot, except for a total melt down that was repaired with a new MAS(FPR went south) and intermittent stalling that was solved with a new OVP.

I went ahead and did the "throw parts" approach simply because I had owned the car for 8 yrs. and knew the ign. system stuff could probably use a refreshing.

Cold, semi-rough idle continued after the ign. system work, so I took the snake oil approach with the 44K. Was lured in by all of the "miracle claims". The 44k did not resolve the semi-rough, cold idle problem, so I thought I'd give it another go, only this time using the Berryman's simply because I had a new can of it laying around and it was MUCH less costly than the over-priced 44K.

Your point is quite valid...why not test spray pattern and I'll do that a tank or two down the road. For now, I'm trying to line up repair facilities that do CIS/FI cleaning(and do it WELL) in the event their service is needed.

Thanks for your reply.

#4 03-01-2006, 01:54 PM

Hi Mike,

Fair enough. I did some reading and found this article interesting. It is from somebody with a product to sell, so consider the source...

http://www.chevron.com/products/prodserv/nafl/auto/content/fueladd.shtm

What kind of gas are you using? I have had very bad experiences with low grade gas (EDIT: particularly in the wintertime),I don't mean octane levels, and now I only purchase this stuff...

http://www.toptiergas.com/deposit_control.html

These guys seem to have a service like the sort you want. No affiliation, but a 100% ebay rating over 500 sales is tough to get-so they must be doing something right?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33554&item=7997499157

This is the flow bench they use:
http://www.niehoff.com/whatsnew/whatsnew1.html

Let us know how things go if you send the injectors off! They apparently give you a before and after flow sheet.

cheers,
dan r.

Mike Murrell · #5 03-02-2006, 01:26 AM

Dan:

Thanks for the injector information.

I'm for the most part, a Chevron-kinda-guy, but do use Shell maybe every 3rd or 4th tank - 93 octane in both cases.

I ran across an article on the WEB one night maybe a yr. ago that was written by a Mobil engineer. I may have seen it here - don't remember? In it, he said to switch brands of gas periodically as different brands contain different cleaning agents and that over time, the same fuel wouldn't necessarily have the same affect as another as far as cleaning goes.

I bought into it simply because he wasn't trying to slam Mobil down everyone's throat and his theory sounded plausible.

It's likely going to be awhile before I ship of the injectors. I've got about 400 mi. of driving to do before I kill the current tank of gas and will likely run another tank or two through it before I start looking at spray patterns.

I'll update this thread if I end up pulling/shipping them for legitimate cleaning.

joel · #6 03-02-2006, 01:57 AM

Quote:

Originally Posted by Mike Murrell

Dan:

Thanks for the injector information.

I'm for the most part, a Chevron-kinda-guy, but do use Shell maybe every 3rd or 4th tank - 93 octane in both cases.

I ran across an article on the WEB one night maybe a yr. ago that was written by a Mobil engineer. I may have seen it here - don't remember? In it, he said to switch brands of gas periodically as different brands contain different cleaning agents and that over time, the same fuel wouldn't necessarily have the same affect as another as far as cleaning goes.

I bought into it simply because he wasn't trying to slam Mobil down everyone's throat and his theory sounded plausible.

It's likely going to be awhile before I ship of the injectors. I've got about 400 mi. of driving to do before I kill the current tank of gas and will likely run another tank or two through it before I start looking at spray patterns.

I'll update this thread if I end up pulling/shipping them for legitimate cleaning.

I've read it somewhere, maybe at this forum, that replacement cost and cleaning cost are not far apart.

Mike Murrell · #7 03-02-2006, 11:22 AM

Joel:

I would not be a bit surprised to learn this is true. I suppose I'll have to weigh the price AND consider the REAL VALUE, if any exists in cleaning 15 yr. old injectors, if & when the time comes.

Thanks.

joel · #8 03-02-2006, 11:35 AM

Quote:

Originally Posted by Mike Murrell

Joel:

I would not be a bit surprised to learn this is true. I suppose I'll have to weigh the price AND consider the REAL VALUE, if any exists in cleaning 15 yr. old injectors, if & when the time comes.

Thanks.

Mike, keep us posted. I pondered upon doing this before, but I recall reading that new injectors are not just "plug and play," kinda thing.

Mike Murrell · #9 03-02-2006, 12:57 PM

Joel:

I hear ya and have read many posts here that claim new injectors need to be primed/bled. In those and other posts, there's a counter argument. The elect. fuel pump will prime the GAS system. It may take a bit of cranking, but after a brief period, the system becomes fully presurrized and the car fires up.

Last year I had to pull the top off of a '95 Isuzu Rodeo 3.2l motor. This included the plenum(air feed) and the fuel rail + injectors. I do realize this is not a CIS system, but it is FI and under pressure.

When I put it back together, I was surprised at just how little cranking it took to get the motor running again.

Look at the following thread and in it, comments made by "mpyne". His profile indicates 29 yrs. experience working on MBs for a living.

How to bleed fuel injectors?

lkchris · #10 03-02-2006, 02:12 PM

Cost of injectors is $36 each.

I think you should replace seals whether cleaning or replacing.

atikovi · #11 03-02-2006, 02:32 PM

I’m not too sure how effective the one-time stuff you pour down the gas tank would be since it’s rather diluted by the time it reaches the injectors. (If it WAS a really powerful chemical you can be sure they wouldn’t sell it over the counter, just to professional shops.) And gas is expensive enough without spending money on some additive every tank full. Most mechanics use fuel injector cleaner that connects directly to the fuel rail and car then runs entirely off this cleaner for 5-10 minutes for a thorough cleaning, however nothing beats removing the injectors and having them ultrasonically cleaned, flow tested and the spray pattern checked. I’ve used http://cleaninjectors.com on V6 Alfas with good results. It comes out to about $12 to $14 per injector when you factor in shipping.

Mike Murrell · #12 03-02-2006, 04:05 PM

I contacted Tim @ cleaninjectors.com and asked about having CIS-E injectors cleaned. Here's his response:

Mike,

Honestly, I have attempted cleaning them, with fairly poor success. I did have a CIS car I was driving and it got to the point it would barely run. I did clean the injectors and bought myself a little time, but that is about the best I can say. If you want me to try, I'll be glad to see what I can do, but they just don't respond very well. The best solution on CIS is new injectors but watch out for the prices!

Tim

atikovi · #13 03-02-2006, 06:23 PM

I guess the mechanical CIS injectors are harder to clean than the Alfa electronic Jetronic and Motronic ones. But then the Alfa injectors cost over $100 each.

S-Class Guru · #14 03-02-2006, 09:13 PM

I installed new injectors in my '91 300SE a few years back. Very straight-forward repair, no priming or anything required at all. just bolt them in and go.
I had a very slight stumble at warm idle, and sometimes it would chug for a few seconds at warm or cool startup. Both problems pretty much went away.
Now, after another 50k miles or so, I am noticing the same symptoms.
back then I paid $21 each, now over $30 is best I can find.
Saw an add in eBay, a guy in England sells them, if you're gutsy.
still, $36 each ain't so bad every 10-15 years or so.

Oh, this chugging at start-up has me kinda thinking it's not just the injectors.
doesn't do it cold, just when warm, or kinda warm, when the idle speed isn't increased. if you give it some throttle it kinda clears it's throat, and seems to fire 3, then 4 then 5, then 6, and all is smooth. Could it be the fuel metering thingy?

DG

carusle · #15 03-06-2006, 10:42 PM

I want to hear the end of this. My 90 300SE does the same thing. OK cold, after it heats up it stumbles and when I give it gas it seems like it kicks in one cylinder at a time until it gets up to speed then it will fly.