Techron fuel systems cleaner. That good or is something else going on?

[Starless]

Well, a few week ago while on the interstate, I down shifted to 4th in my SC to pass a row of trucks. It got to 4000 rpms and that was it. After exiting the highway i tried to rev in all gears but 4K was all she had. Even then it felt flat. I really have had no time to look into the car so I replace the cap and rotor as I had them laying around to see if maybe that was the issue. Nope. Maybe bad gas? So I filled it with some "top tier" gas and drove it for a few days. Nothing. It was actually getting worse. The first couple of minutes of driving it would stumble pretty badly. With no real time to put into it I was ready to call my shop to have them look at it. Then I found that I had a bottle of Techron fuel injector cleaner and one Complete Fuel System Cleaner. With nothing to lose and a quarter tank of gas, I poured the complete system cleaner in. I drove for maybe 50 miles in a period of 4 or 5 days and all of a sudden the thing woke up. And I mean a night and day difference. I pulled in to pick up some take out and when pulling out of the parking lot It felt smooth, so I punched it and hit redline. It also sounds different, throatier. It's been fine for a week now. So, is it possible that the Techron made that much of a difference or is there something else i should be looking for?

[cabmandone]

I've never personally had the stuff make a difference in any vehicle I've used it in. I'd think if you had an injector or several injectors plugged to the point of causing a performance issue that one bottle wouldn't fix that problem.

My money would be on the problem showing up again. BTW, you might ask the mods to move this one to the tech section. Not that there aren't a lot of guys in OT that know what they're talking about, It's just that you might get more of the gurus who don't come to OT to chime in.

[Starless]

I just realized I posted in OT. Thanks.

[cabmandone]

Just fire a PM to Seahawk and he'll getcha where ya need to be.

[mattdavis11]

Catalytic converter

[Scott Douglas]

I run Chevron gas in our cars almost exclusively and have never had a problem, and that's a cumulative 500k miles or so, mostly Honda's with an occasional Porsche thrown in the mix.

[LWJ]

It is not the gas additive that did this. Something else caused it, and then changed back.

The CIS injectors are big, sloppy, and not precise like modern injectors. The whole CIS system is wonky as heck and problematic if things are off. Example? I had a cracked airbox on my 80 SC. It took me (and some well known 911CIS "experts") way too long to figure this out.

You need to review things from a baseline and move forward.

Spark and fuel are where to look. I never heard of compression going bad and then good.

[Starless]

Yeah, I didn't think a bottle Techron would make such a difference. I was thinking maybe the fuel filter. Leaving for vacation Monday so not much I can do right now, plus it's running great, so a bit harder to trace a problem when it's not acting up. I guess I'll just wait for the symptoms to reappear and take it from there.
Thanks

[IROC]

I will say that I had a similar experience once. I was at a 2-day DE/time trial and my car started running really roughly near the end of day 1. That evening I had my region's tech expert (who owned a Porsche repair shop) help me troubleshoot and he suspected a clogged injector. This was on a stock 2.7 CIS engine. He suggested running a bottle of Techron through it. I left the track, bought one of the large bottles of Techron and poured it into well less than half a tank of gas. I drove it around for a while and it cleared it up. Ran fine the next day at the time trial.

Maybe coincidental, but it seemed to be very well correlated.

[Rodek]

You may of had some carbon build up or fouling of the spark plugs and the cleaner cleared some of it away.

[Tom_in_NH]

The Techron may have dissolved some gunk from the tank, and may now be clogging the filter.

[deemsriddle]

Yes, it can make that kind of difference. I have been using Techron for 50 plus years in my cars and have recommended it to others with surprising results. In fact, the Porsche factory service bulletins used to recommend Techron in Porsches that were running poorly in the "bad gas" era. Decades ago, the auto manufacturers imported Chevron gas to run the EPA tests as Chevron was not sold in that area.

[Sunroof]

Their are an abundance of comments and noted experiences of using Chevron Techron on this board. Let me begin by saying that many decades ago (70's) Porsche put out a bulletin on the use of Chevron Techron as a routine injector cleaner.

Here is my Chevron Techron story.
To begin with, I have owned either a 944 (1985.5) and three 911's (1973.5T, 1974 and 1979SC) over the past 40+ years and all these cars have benefitted from Chevron Techron.

I sold my 1985.5 944 with 365,000 miles on the odometer to my mechanic who never performed any engine work aside from a blown head gasket! I thank Techron for the long engine life. Techron does not combust in the chamber, but weeps past the rings as it cleans the injectors and enters the chambers. The odor of Techron is quite apparent on the oil dipstick as it settles in the oil sumps. What I often recommend for those who never added it to the fuel is add the BIG BOTTLE to the fuel a few hundred miles before an oil change.

Now we have Sea Foam and many other cleaning products that are chemically similar to Techron and some say that Sea Foam works even better. I know BMW puts out a concentrated cleaner as well.

So, yes, Chevron Techron can save the day and keep your injectors and your cylinders clean.

Bob
1973.5T

[Starless]

Originally Posted by Tom_in_NH

The Techron may have dissolved some gunk from the tank, and may now be clogging the filter.

It's been running fine SINCE I added the Techron.

Well, thanks for all the replies. I guess there are quite a few opinions on the matter, but since it's running great at the moment, I'll just keep driving it and see if it reoccurs.

[donbecker1234]

Originally Posted by Starless

Well, a few week ago while on the interstate, I down shifted to 4th in my SC to pass a row of trucks. It got to 4000 rpms and that was it. After exiting the highway i tried to rev in all gears but 4K was all she had. Even then it felt flat. I really have had no time to look into the car so I replace the cap and rotor as I had them laying around to see if maybe that was the issue. Nope. Maybe bad gas? So I filled it with some "top tier" gas and drove it for a few days. Nothing. It was actually getting worse. The first couple of minutes of driving it would stumble pretty badly. With no real time to put into it I was ready to call my shop to have them look at it. Then I found that I had a bottle of Techron fuel injector cleaner and one Complete Fuel System Cleaner. With nothing to lose and a quarter tank of gas, I poured the complete system cleaner in. I drove for maybe 50 miles in a period of 4 or 5 days and all of a sudden the thing woke up. And I mean a night and day difference. I pulled in to pick up some take out and when pulling out of the parking lot It felt smooth, so I punched it and hit redline. It also sounds different, throatier. It's been fine for a week now. So, is it possible that the Techron made that much of a difference or is there something else i should be looking for?

Comparison of Bosch CDI to CDI+

Thought of this as even after you replaced rotor you were seeing some sort of limit at RPM.

[icarp]

I just had a customer car with the same problem .
1980 sc , clogged fuel filter , very clogged , could not blow through it
Ian

[milnejk]

I had similar problem and the fuel filter was the problem. No downside to changing it especially if it has been a while since changed.

[82 sportsc]

Been using Techron for over 10 years…..I store mine over winter so often find a check engine light in Spring on Boxster S, 911C4S and wife’s MB 350…I get fresh gas and appropriate amount of Techron
Usually next day after 1 hour run or a couple of days driving check engine light gone !

[moparrob]

I had the same experience (pretty much) as you, so I am also a believer. My belief is that there was a clog in either the fuel distributor or an injection nozzle. All I know is it worked, and was relatively inexpensive.

I also run Chevron gas exclusively now.

[MichaelSJackson]

I once bought gas with water included. Brand name station; I don't go to that particular station anymore. She ran terribly, just leaving the station. So I bought a bottle of HEET. (My brother uses it in his marine engines up in Sitka.) Straightened things out in short order. Perhaps Techron has some of the same water encapsulating properties?

I'm a Techron user. Usually buy Chevron. Had heard/read that Porsche gave it a thumbs-up. Will buy a bottle about once a year. I've also heard that the formula sold at the station is different than on the autoparts shelves. Don't put much weight in that, but I purchase it so seldom that I buy from the Chevron stations.