odd Loss of power after rebuild

[wolfsbergjettagli]

Hey Gents!

im still milling over this same problem. after rebuilding the top half of my 1990 Jetta 2.0 9a i started having an issue with loss of power car starts and idles good. i get on the road and after a few seconds in any gear i have an instant loss of power (feels like its retarding) that continues for about15-30seconds then a little surging and returns to normal.
this happens hot or cold.

Replaced due to bad condition or out of spec
02 sensor
temperature sensor
both knock sensors (torqued to bentley)
crack position sensor
new ignition wires
cap and roter both have less the 5000 miles on them

mechanical timing is set correctly to bentley and ignition is set 6+-1 degrees BTDC
and i checked for vacuum leaks

has any one had this problem? ill be great full for any help i can get.

[ps2375]

9A has a crack position sensor? (oh, I think you mean crank position sensor). I'll ask it again, 9A has a crank position sensor? When did this happen?

[wolfsbergjettagli]

no ur right is really called "Knock Control Reference Sensor its on #4 wire" sorry for the mix up

[ps2375]

I don't know the 1990 car's , CIS-e? Have you physically removed the intake boots and checked for tears?

[wolfsbergjettagli]

i bought a new one that goes over the distributor, checked the hard plastic tube and then the one that attaches to the throttle body for leaks many times taking them off and inspecting them. there wearing but no cracks that show through.

[wolfsbergjettagli]

Cis-e Motronic

[ps2375]

Seeing that it is 22yrs old, I would check the engine's wiring harness top to bottom for anything not correct, cracks in insulation, chafing,,,anything and fix those. Intermittent issues can be difficult, this could be quick and easy or hard, I would be ready for the latter. Have you checked the dpr voltage, and you might want to rig up something to check it while you are driving and would be good to see what it is doing when the problem happens.

[nmwstunna]

Man I got the same problem an cannot figure it out. I hope we come up with a solution.

[wolfsbergjettagli]

i will have to try hooking up the DPR as i drive, shouldn't be hard i already have the test harness made up

nmwstunna what r u driving and what have u done to diagnose are issue? right now im trying to identifie which system is at fault for this problem. fuel or ignition

[nmwstunna]

I have a 90 GLI 16V with TTchip. I have just beenn looiking of all wires. I want to hook it to a cpu to scan for any codes have not had time to go by this shop with the plugs. Oh also what is your mpg's.

Thanks

[wolfsbergjettagli]

i have a custom trans buit with a taller fifth gear so around 26-27 combined. i get alot of highway living in texas. i have a guy a vw Austin that wants to check and see if his old computer for these cars still works so i got a free read . im thinking of having this done on wednesday so ill let you know what we find out ASAP.

is it possible to get pictures of the wire hook up's for your ignition coil and the vacuum line that goes to the brake booster. my poor jetta has been heavily abused and neglected by both its PO's so i need some reference pictures.

ill send you my personal email for ease of transferring the pictures i you agree.

thank you

[wolfsbergjettagli]

i have an old vw brochure that states 22 city 28 highway 24average. im getting i around 30 highway from a 400 rpm drop in fifth.

[slvrarrow]

Same problem tried brain, dizzy, CTS, will try coil tomorrow and see?

[91JET16V]

I'm just going to toss this out because you didn't mention it, how about your sparkplugs? Kinda sounds like it's dumping fuel and loading up and then cleaning it's self out?

I'm also running a higher 5th gear tranny and pulling 30-32 mpg spinning about 2500@65mph, I have a almost totally flat 30 mile commute.