86 with loss of power

[CaptDon]

I have an 86 Cabriolet with an automatic transmission that I recently purchased. Ran great when I bought it but I like a clean engine, (engine and transmission don't leak, just normal dirt from years and years of driving. So I sprayed it with engine de-greaser and sprayed it with high pressure water several times. The engine is nice and clean, but now it just lacks the power it had before I cleaned it. The ignition wired were leaking, so I replaced the plugs, cap, rotor, and wires with no real improvement. The engine is good and dried out, starts fine, idles fine, just a lack of power. I also clecked all the electrical connctions and cleaned them to ensure a good connection. I also first thought I might have warped the head and blew the head gasket because the engine was warm when I cleaned it. Ran a compression check cold, 130-140 PSI, ran another compression check with a hot engine after about 50 miles and all the cylinders checked at 160 PSI. No water in the oil, no oil in the coolant, no overheating, Any ideas?

Don

[Briano1234]

Other than still having water or cleaner in one of the many connectors, Check for vacuum leaks, and check the timing....

I too have 2 automatic cabbies and I clean the engines with power washers and cleaners. I have had the loss of power issue, but It is because I have missed a wire that was wet. I use a product called Wire dryer by CRC, I spray every wire and connector after I clean them... Also prior to washing I spray all the wires with WD-40....

I bet that you have gotten water in your fuel distributer, and the micro screen... Ron or William can be more of an assist on the CIS engines.... I am a Digifart kinda guy... One thing that may help is wait for dark, and start the car. with no lights in the engine compartment. If you see little sparking tracks after you start the car then once you eliminate those you will probably gain power.

[CalAltaDubber]

Welcome to TRF.

I think Brian has you covered pretty well. The only thing I would add is to check the coil. Make sure it isn't cracked. if it is it will arc and degrade your performance.

[gull]

Make sure you didn't knock a vacuum line loose with the high pressure hose. Also check the accordion boots that go between the fuel distributor and the intake manifold. Finally, make sure your air filter isn't soaked.

[CaptDon]

One thing I've noticed.....the exhaust pipe outlet is extremely clean. I'm thinking it possibly could running lean, (starts up, idles OK, just no power and slow to rev-up). What could I have done to cause this by cleaning the engine? I haven't had the time to troubleshoot anymore, but may be this is another clue. I'm thinking of taking it to an independent VW mechanic here in the San Diego area and see if he can figure it out. I would really like to get the car back on the road.

Don

[gull]

Lean running might point to a vacuum leak causing "false air."

[kamzcab86]

Ditto on the vacuum leaks and timing.

[gull]

Was '86 a CIS-Lambda year? If so, you also want to make sure the oxygen sensor connector isn't full of water. Problems there can create some mysterious driveability problems. The wiring harness for the oxygen sensor is under the intake manifold on the right side of the car (passenger side, in the U.S.). The wire comes off the sensor, which is in the exhaust manifold, and will meet some kind of connector. The exact sort of connector here may depend on who last replaced your sensor, but it's usually a sealed push-on type. If the rubber boot is old it may be full of water.

[kamzcab86]

Was '86 a CIS-Lambda year? If so, you also want to make sure the oxygen sensor connector isn't full of water. Problems there can create some mysterious driveability problems. The wiring harness for the oxygen sensor is under the intake manifold on the right side of the car (passenger side, in the U.S.). The wire comes off the sensor, which is in the exhaust manifold, and will meet some kind of connector. The exact sort of connector here may depend on who last replaced your sensor, but it's usually a sealed push-on type. If the rubber boot is old it may be full of water.

All CIS Cabriolets are CIS-Lambda.

[CaptDon]

I don't think it's a water issue because it's beem over a month since I cleaned the engine, and I've driven it probably 150 miles. I'll give the vacuum likes a good looking over. I gave them a quick look, and I don't hear any air sucking noise.

Thanks for the idea, and when we figure it out, we'll ave a winner!

Don

[CaptDon]

Problem solved! Decided to take the car to VW Paridise in San Marco's Calif. to get it checked out, (couldn't find any smoking gun by myself). They found the #2 injector clogged. I had them clean all the injectors, and tune-up/adjust the fuel injection system. Problem solved!

Don

[gull]

Problem solved! Decided to take the car to VW Paridise in San Marco's Calif. to get it checked out, (couldn't find any smoking gun by myself). They found the #2 injector clogged. I had them clean all the injectors, and tune-up/adjust the fuel injection system. Problem solved!

Don

Great!

I've found it's really hard to troubleshoot CIS piecemeal. Often the only solution is to go through the whole system, checking everything and fixing anything that doesn't seem right. I think this is because often a lot of small problems stack up to create one big symptom. I'm glad you found a mechanic that understood this. Often people who are used to more modern systems will just start replacing parts, which gets expensive fast.