77 campmobile 2.0 ltr FI problems

[Amskeptic]

Brian, didja ever get this bus straightened out? If not, the following is a trump card

. . . I will drive my ass down to Florida and you WILL give me a cup of coffee if you do not have a beautifully running bus . . . . by let's say, October.
Colin

Well? Brian?
Colin?

[buck]

Status update - Bus still not running correctly. Retrieved old AFM from VW Dealer as I believe it to not have been the problem. New AFM has been adjusted so much it will take some doing to get dialed back in. Re-read all the previous replys and info contained within. Realized I better start back from beginning; previous PO's efforts, my efforts, parts checked for proper operation, parts replaced, engine settings, etc..... Got burned out, depression set in, contemplated getting rid of bus. Moved on to another project (building 12' wooden boat). Wife motivated me by mandating " get it running, or get rid of it." Found several manuals on the net about the Bosch L-jet. I now have complete knowledge of theory, design, what/why/how/when the L-jet does, but most importantly when it "does not". After complete, methodical, and thorough testing of components of the L-jet system, I now believe the problem lies in the cold start valve and injectors. The CSV is not working at all, and the injectors are squirting a thin stream. This is my theory: Cold start sequence not working, injectors partially clogged, engine start up ability severely impacted by lack of cold start components, engine runs lean due to clogged injectors struggling to squirt proper amount of fuel. My previous adjustments to AFM were trying to adjust system to get more fuel with the assumption ECU wasn't receiving/transmitting proper input/output. Reality was ECU was operating correctly, but fuel injectors couldn't squirt enough fuel. So, engine didn't spin enough RPM/suck air to tell AFM that it needed more fuel. So new CSV, thermo time switch and injectors on the way. Motivation high, depression low. I'll keep you posted on latest efforts

[midatlanticys]

Brian, Well done!! I like the new approach. . . . and I'm really pleased the original AFM is back where it belongs. . good luck with resolving this - it'll be well worth all the effort you've put in so far.

. . . and if you really want to do the bus a favor, give some serious thought to having Colin swing by on his IAC - in his own words

There are some good reasons to consider this visit as an investment rather than an "expense".

"

[Randy in Maine]

Did I miss the part where you checked the dwell angle prior to setting the timing?

[buck]

Dwell angle set w/ new Acton multimeter/auto analyzer. Timimg initially set w/ feeler gauge and then adjusted to 44 degrees w/ meter. The Acton meter is a great tool for the money.

Buck

[buck]

All,

1977 Campmobile is running correctly. FI problem appears to have been clogged fuel injectors. Put new injectors in, new CSV, verified proper operation of AAR, hit the ignition and the bus fired right up, idled effortlessly, revved easliy. Initial test ride revealed great acceleration thru all gears, top speed of 70 mph, no bogging or hestitating. Second test ride was approx. 100 miles thru the NW Florida countryside. Bus ran flawlessly. Smooth thru all gears, great acceleration, comfortable cruising.

PO had replaced fuel filter, fuel pump, and injectors, so I had always assumed they were OK. Looking back at how rusty the fuel tank was, I should have suspected the fuel injectors. I guess enough small stuff got through the filter and pump and clogged the injectors.

So here's to all who offered advice, encouragement, and help. I appreciate it!!! I have learned a lot about VW buses and the Bosch L-Jetronic FI system in last three months thanks to the many VW websites, Bentley's repair manual, and various local VW enthusiasts. More than I ever dreamed. It has been an empowering experience.

Of course the thrill of victory was short. Post check ride inspection revealed a sticky brake caliper on the front driver's side. Not bad, just enough to heat the rim up a little. Checked the rubber hose section of brake line and it appears clog free. Problem must be in pistons/seals, probably from sitting up for so long. Unfortunatley, I am having trouble breaking the caliper mounting bolts loose. Bathed them in PB blaster and put the impact driver to them, but could not bust them loose. Any ideas?

Brian

[Amskeptic]

All,

1977 Campmobile is running correctly. I am having trouble breaking the caliper mounting bolts loose.

Get your BA breaker bar and go to town on them. When you reinstall or replace caliper, do not go as ape on them as you had to to loosen, 100 ft lbs is fine.
ColinCongratulationsByTheWay

[buck]

Brake caliper bolts busted loose. Bought a new 500 ft-lbs impact driver and the bolts came out like they had been coated w/ anti-sieze. Got one piston out, the other is being more difficult. Any tips?

Brian (soon to be bus riding)

[Amskeptic]

Brake caliper bolts busted loose. Bought a new 500 ft-lbs impact driver and the bolts came out like they had been coated w/ anti-sieze. Got one piston out, the other is being more difficult. Any tips?

Brian (soon to be bus riding)

Air pressure + block of wood to catch it. You may need to re-piston the other bore to allow air pressure to build up. Careful.
Colin

[Gypsie]

Might try using the brake system to push is out by reassembling without pads and if possible, no disk, hold the side that moves easily with a c-clamp or ???... then pump it out.

I once ended up grabbing the outer lip of the piston in a vice and tapping (read tapping not whacking..) around the caliper with a drift...bit by bit