tsb# 1234567



affected vehicles: anything with a bosch fuel pump



we regret to inform you that running a bosch pump may lead to the pump wearing out prematurely, and to a loss of fuel flow and pressure.



symptoms: taking car to dyno and not being able to tune past xx(low psi) due to running out of fuel, despite bosch pump and large injectors.



diagnosis: with the fuel return line pinched off the pump should be able to make more than 90psi.



correction: replace bosch pump

the 3 rotor was a little too thirsty eh?

no it wasnt my car. 40,000mile fd with a bosch pump, pump was too worn out to go over like 10psi....

What was the PN on your bosch pump? I had 3 bosch pumps on my car and didn't have any issues. I had 1 bosch 61 979 pump feeding a fuel catch can and 2x bosch 61 984 pumps feeding the engine. The 979 pump is rated at 165lph and the 984 pumps are rated at 228lph @ 73.5psi. Did you only have 1 pump on your car? Where did the above information come from?



-Destin

Here's a graph showing the flow rates between a stock 3rd gen fuel pump, walbro gs341 pump, and a bosch 220lph pump. The bosch pump outperforms most other pumps at higher pressure. There must have been something faulty with your buddy's pump.



-Destin

yes thats what i'm trying to tell you. the pumps wear out, check yours before you loose the motor.

Bosch makes oem fuel pumps for Prosche, Saab, Benz, and may other high end cars. Do you think they would put crap in those cars? Bosch specializes in fuel components.

They created the first fuel injection system in 1967. I don't think they would still be in business today if they sold crap.



Was your buddy running an inline fitler before the pump or just the oem filter after the pump? If not it may have gotten contaminated which will cause premature pump failure. Also if the pump didn't see enough fuel it may have overheated and failed. Fuel is used for lubrication and cooling of the pump.



-Destin

have you ever owned a german car?

Me, no. I drove my dads Audi when I was younger and i've driven plenty of VW's. What relevance does that have to the product quality though? none. Do you have any proof that there crap or are you basing everything off one incident?



-Destin

the #1 no start/stuck by the side of the road for a german car is the fuel pump, they do fail regularly.



however ive never seen a pump that wore out. we have one bad worn out pump, and the tuning shop had seen a few too. last time the car was there they tuned it to 14psi, this time they couldnt get it up to 10.....

Spending most of my life thus far in the SF bay area where there is a large population of german cars, and I can't tell you how many bosch equipped vehicles I saw getting towed because the fuel pump failed. I knew 2 people that had their pump fail in their German car's.

Just because its German and goes on cars that are marketed as "high end" does guarantee they wont fail. Hell, all of those pumps I saw had a "Made in CZ" sticker on it!!!



This is good info for all you guys running those pumps, might want to keep tabs on the PSI output...

i like how he mentioned porsches...like they never have any problems...hello oil leaks.



kevin.

LOL. reminds me of my last job. This guy always parked his 911 in the same spot everyday. And boy was it obvious. It looked like a baby valdez ran aground....

I can also tell you that a friend of mine who owns a repair shop specializing in BMW,MB,etc... replaces a fuel pump just about every week on BMWs.

I don't really care if its a bosch pump or any other pump, fuel pumps go bad eventually. Thats why its always smart to have a fuel pressure gauge whenever you're running these higher flow pumps or pushing higher horsepower.

anything that moves eventually wears out, regardless if it was made by germans, japanese, chinese, americans, canadians, doesn't matter. Everything has a life cycle. So called high performance designs push this boundary more... if it ouputs/flows higher you had to scrafice something to get that. In this case it appears to be life cycle.

right but



a) it seems to be short

and b) it doesnt seem to fail like everyother pump.



for the record my dad has 2 gas mercedes, and every fuel pump on both cars has been changed

Had Bosch pumps on mutiple cars of my own, stock and upgraded, RX-7's in town with 12K miles on at least two. No issues. I would insure your wiring and voltage is going through something other than stock wiring when in an RX-7. Helps having a pre-filter too. Law of large numbers says that your experience may be accurate for any fuel pump, but not enough for a pattern for a specific make/model. Good luck with the new setup.

This reminds me of the lady who needed repair work on her car. Her response was "But... it's a TOYOTA!"



As if the badge on the grille makes one bit of difference. Mechanical items can and do wear out, no matter who made them or what kind of vehicle they are on.



Bosch also makes fuel injectors for Ford. I suppose they never go bad, either? (I have a stack of them that says they do!)



I am curious what your measure of "the first" fuel injection system is. If you mean electronic, you may be right. But Bosch's K-Jetronic system started out life as the Rochester mechanical FI that Chevrolet introduced on certain 1957 models. When Chevrolet abandoned the system due to poor cost effectiveness, Bosch bought the rights to the unit and started tinkering. Of course, fuel injection goes beyond 1957, as many WWII tanks and aircraft had fuel injection, as well as every diesel engine ever made.



Bosch makes good stuff, but good does not mean you can install it and forget about it. Every Bosch pump I've seen installed in a vehicle has been extraordinarily overkill for the job. I would not doubt if they did that deliberately to make the pumps seem to last longer, given that they would still have enough output for proper engine operation if it was at even 50% of original capacity. When you're pushing the limits of capacity, even a few percent can hurt.



Since in this instance the pump could not even provide 10psi, I wonder if the safety blowoff was lodged open by debris. Only a scope on the pump wires could tell you for sure, even if it was just for academic reasons.

d jet is 1967 i think?

i have no experience besides my dad's audi's that always had fuel problems with the RETARDED mechanical fuel injection.....

[quote name='vosko' date='Mar 19 2005, 05:11 PM']i have no experience besides my dad's audi's that always had fuel problems with the RETARDED mechanical fuel injection.....


[/quote]



G'day from Germany ! I'm a Mazda Rotary driver... and they are some reasons for it.



REgards

Iwan