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Bosch 0 280 155 811 Injectors

Been running these injectors for awhile now. Buick 3.0 Bar FPR, BMW white connector ECT, Open breather filter on valve cover. Toyota Supra Twin Turbo PCV valve mounted between block mounted oil separator and intake manifold vacuum port using 3/8 inch nipple (with vacuum pump intake filter fitted in the middle). Nipple on turbo inlet hose plugged. Been messing with adjusting the baseline fuel mixture. I have been enriching the mixture about a quarter turn using the AMM pot screw at the last 3 tank fillups. Every time I turn the screw another quarter turn clockwise i get .2 more miles per gallon, so far up to 24 mpg average on the last tank. I figure to keep enriching the mixture until the mpg's start to drop.
 
While replacing my 30k mile Autolite XP63 spark plugs with a new set I had on hand I found that number 4 plug had lots of white ash deposits. So I pulled the fuel rail to swap in a spare injector to replace number 4. Engine idles better, vacuum test gauge shows a steady 20 inches of vacuum at idle. Next I needed to reset the baseline fuel mixture. Managed to start with a baseline setting of 385 ohms at the AMM pot screw. Figure I'll end up with a baseline setting near 300 ohms (calculations show 298.67 ohms needed).
 
A day later and i had the top o-ring rip on number 4 injector and spray fuel when trying to start engine. Engine started but I smelled raw fuel, looked out drivers window and saw fuel running out from under car. Shut off engine, went to work fixing the problem. Had to pull injector rail in nursing home parking area before I could leave. Had 0-rings with me. Figured out that to be safe these injectors need one o-ring on the top and 2 o-rings on the bottom of each injector. So removed the o-ring spacer which is half as thick as 0-ring and installed to bottom 0-rings.

Everything seems to be secure at this time.

As far a baseline fuel mixture my calculations may have been incorrect. I was using 385 ohms as baseline starting point then remembered that when i had removed the plug from the AMM the baseline setting was 269 ohms. So 21% [300.6/363.1] more fuel should result in 269x.79=212.51 ohms
baseline setting.
 
Since fixing the leaking injector problem I've been averaging 24 mpg. But the hot restarts were acting like too much fuel. Cold start may have been too much fuel.

Yesterday I swapped the Buick 3 Bar FPR to the BMW 2.5 Bar (actually tests at 2.7 Bar/40 psi) fuel pressure regulator. The idle is much better, the running is much better, and cold and warm restarts are much better. Managed a 15-20 minute warm restart without issue.

Still tuning the AMM pot screw and checking the mpg's on tankful.
 
Yesterday I swapped the BMW coolant temp sensor for the correct LH 2.2 sensor with blue connector. This made an improvement in the idle quality.

Bosch 0 280 155 811 injectors
BMW 320i 2.5 Bar (tests at 2.7 Bar) fuel pressure regulator.
 
Note to self: Get rid of all BMW fuel system parts so that I don't keep trying to use them expecting a different result.

Today I swapped back to the GM 3 Bar fuel pressure regulator. With the BMW FPR the mpg's were worse and the car seemed under powered. Guessing that these Bosch Gen III injectors which are rated at 36 lb/hr at 4 Bar aren't very efficient at less than 3 Bar.

Fuel flow calculator shows:

Old fuel flow: 42 lb/hr at 58 psi (441 cc/min at 4 Bar)

new fuel flow: 36.38 lb/hr at 43.5 psi (382 cc/min at 3 Bar)

These same injectors are used in GM LS3 at 4 Bar (58 psi).
 
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Found best running with these injectors is with:

Bosch 0 280 160 226 2.5 Bar FPR from BMW 318i

Bosch 0 280 130 023 coolant temp sensor with white insulator from BMW. Replacement may have green insulator. Has narrower tolerance than 0 280 130 026.

NAPA interchange for Bosch 0 280 130 023:
NAPA ECH TS5520 for 1984 Volvo 760 (black insulator)
NAPA MPE TS5520SB for 1984 Volvo 760 (white insulator)

1950 Ohms @ 77 degrees F
225 Ohms @ 200 degrees F

0 280 130 023 was used in:
Alfa Romeo
BMW
Bentley Turbo R
Bertone X-1/9
Chevy
Datsun
Ferrari
Fiat
Ford
GMC
GEO
Honda
Hyundai
Infinity
Isuzu
Jaguar
Kia
Lancia
Mazda
Mercury
Nissan
Opel
Peugeot
Pininfarina
Pontiac
Porsche
Renault
Rolls Royce
Saab
Subaru
Suzuki
Toyota
Triumph
VW
Volvo
Yugo
 
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BMW temp sensor and 2.5 Bar fuel pressure regulator going well.

Tested the fuel pressure or BMW 2.5 Bar FPR with tester. 36 psi with vacuum connected. 39 psi with vacuum disconnected.
 
Update:
Car was running fine in decent weather. As soon as it got colder the MPG's dropped to 18. When it was cold outside it seemed to have less power when pushing against the wind. I had also noticed that if I passed a vehicle black smoke would roll from the exhaust. I had looked around in my stash and found 2 more coolant temps sensors with the correct blue connector for LH2.2.

Today it was nice enough to try swapping the coolant sensor. It was 43 degrees F outdoor temp. I connected the DMM to the blue sensor and I got a reading of 2960 ohms. I connected the DMM to the BMW sensor with the white connector. I got 4560 ohms and still climbing. I took that to be the result of a failed sensor.
 
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Update: Here we are again. After still having the issue that car runs like a fair weather car (good during good weather, not enough power when driving against the wind), I swapped back to Bosch 3.0 Bar FPR from Buick 3.8 V6..

Now 0 280 155 811 injectors 34 lb/hr at 3 Bar, using correct ECT sensor for LH 2.2, and 3.0 Bar FPR. Was able to set baseline fuel mixture.

Thinking the issue with using FPR for BMW was fuel pressure at idle (36 psi) was similar to idle fuel pressure with 3.0 Bar FPR, but, the rising rate didn't supply enough fuel pressure (39 psi) at lower vacuum reading.

Making short out of town trip this afternoon. Will be able to test for cruising power going both directions.
 
Update: No matter what I try the Bosch 0 280 155 811 injectors just won't work at 3 Bar when running LH2.2. Had issues with cold start and what seemed like flooding during warm restart. also had issues trying to get a decent idle. Seems that it was causing the exhaust to bang against the underside of my 88 765.

Tried another 3 Bar FPR with no improvement.

Swapped back to the BMW FPR and idle is good, no hard cold start, no flooding on warm restart,

I'm trying richer baseline setting with the AMM POT screw. I'm up to 301 Ohms now. My math says I can go as high as 333-350 ohms on the basis of initial baseline setting of 385 Ohms. Based on 11-17% increase in flow rate.
 
AMM is adjusted. Idle is great. Cold starts great. Warm starts great. Averaging 20-21 mpg.

Bosch 0 280 155 811 injectors
Bosch 0 280 160 226 2.5 Bar fuel pressure regulator
ECT is OEM with the blue connector for LH 2.2

Would have to check the AMM baseline setting, but it is in the 300 Ohm range.
 
Update: After much testing of the ECT with white connector from BMW I decided to give it another chance. I had forgotten that temp sensors need to be tested in liquid.

After reinstalling the sensor I got the same baseline setting as with the ECT with the blue connector. Although the idle is smoother.

While testing the ECT with the white connector I found that the Ohms reading at 68 degrees F (80 C) is 2840 0hms, and at 176 degrees F (80 C) was 404 ohms which is about equal to the blue connectors sensor at 158 degrees F (70).
 
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Update: as soon as weather permitted I switched back to the ECT with the blue connector. The engine was taking too much cranking to start when cold.

Update: I had been smelling fuel whenever I got near my car. The smell had recently gotten worse. The rain in my area finally stopped long enough for the driveway to dry up. I looked under my car and found fuel dripping from the hose that runs from the inlet to the main pump. Funny thing is fuel wasn't dripping when the engine was running. I bought a length of 1/2" hose from NAPA and swapped the hose. It appears that the new hose has the same markings as the old hose and I remember sometime in the past 13 years buying a length of 1/2" fuel hose from NAPA.

The hose I removed was swollen, separated and split. After seeing the hose I thought that maybe I should have bought better quality hose.

As a side note it appears that the hard start was due to the leaking hose. Now to see if my fuel mileage improves.
 
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After replacing the hose from the metal fuel line to the inlet to the main pump I'm going to have to mess with the baseline setting again. The overly rich smell from the exhaust coming in my car when my brother had the passenger door open to long tells me it is set too rich.
 
Update: After fixing the Fuel hose leak I swapped back to the BMW coolant temp sensor with white connector. Idle is better, still have some more tweaking to do. Average mpg with the sensor with blue connector was 20.
 
Still suspected the BMW coolant temp sensor being defective. I located a sensor with green connector from a Geo Tracker. The specs are similar to the specs of the BMW sensor. The Suzuki OE sensor has the top raised part of the connector offset to the side instead of centered. I filed off the raised part and it fit the wiring connector. I installed this sensor and the idle is now steady and running is great.

I have found the Bosch part number for a sensor with the green connector that replaces the BMW white Connector sensor (0 280 130 023).

Bosch 0 280 130 055 (green connector that fits OE Volvo wiring connector) fits Jaguar XJS 1987-92 5.3L V12. Autozone listing $21.99 at Autozone.
 
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