One year in and still not working ***Split From Lambda system 0 dwell..***

[Simms.justin]

Hello all!

I’m in need of help! I have had the car a year and have put less than 4 miles on it. Long story short is it runs great in the garage but as soon as it gets to temp (200+) it stumbles and loses all power. Seems like it is starving for fuel. I know it’s not the wur (tried three), or the ecu (2 of those), not the relays. Here is everything I have done since I bought the car. Basically completely new fuel system and all electrical stuff I can think of.

So far I have done the following:

Nov 21- April 22

Installed a new fuel pump. Ac Delco mu1777
New battery
New ignition coil
Cleaned out the tank
New fuel sender
Got the fans rewired
New otterstat
Dave McKeen rpm relay
New lamda probe relay
Rebuilt warm up reg
New cold start valve
EZ oil drain plug
Oil change
Plugs
Plug wires
New o2 sensor
Distributor cap/rotor
Stainless fuel lines
New injectors
New fuel accumulator
New ignition resistor (ballast resistor)
New main relay

April 22

All coolant Hoses changed
New hot water valve
New thermo vacuum switch
New vacuum lines
Led door lights
Led side markers
Led front turn signals
New side marker gaskets
Cleaned valley of death (x2)
New cylinder gaskets

May 22

New belts
New idler pulley bearings
New air intake hose (removed stove pipe)
New water pump
New thermostat
New thermo time switch

June 21

New hood hinges
Headlight buckets sanded and painted
New headlight finishers
Led headlight switch
New (used) front fascia
Eyebrow repair kit installed
Led tail lights
New tail light circuit boards
New tail light harnesses
New screw in otterstat/stainless pipe
Rear loom cover
Throttle spool cover
Dave Mckeen Hot start relay

August 22

Windshield replaced
Inner door seals
Outer door seals
A pillars re wrapped
New headliners
New sun visors
Stainless brake lines
Brake system bleed and flush
New spark plugs
New ppr shims and o rings
Eibach shocks and struts
Hand brake adjustment
Small ding repaired on passenger door roof
Fuel pressure test
Injector nozzle test
Alignment
New rear screen finisher
New steering rack
New steering wheel bushing
New tie rod ends
Wheels powder coated
New tires
Carpets cleaned
New parcel shelf carpet
Floor mats
Warm up regulator rebuilt (again)
All new solid state relays
All new fuses
Painted the fascia’s
Cleaned all ground points

[82DMC12]

Hello all!

I’m in need of help! I have had the car a year and have put less than 4 miles on it. Long story short is it runs great in the garage but as soon as it gets to temp (200+) it stumbles and loses all power. Seems like it is starving for fuel. I know it’s not the wur (tried three), or the ecu (2 of those), not the relays. Here is everything I have done since I bought the car. Basically completely new fuel system and all electrical stuff I can think of.



You've replaced an incredible number of parts. I have to ask if you have 1) checked fuel pressure using a K-Jet fuel pressure gauge, and 2) checked base timing and timing advance curve and confirmed there is no timing advance at idle?

Where are you located and have you had another knowledgeable owner come take a look at your car? This should not be so difficult to figure out. There are a number of checks and readings to verify all laid out in the Workshop manual. There is also a troubleshooting guide in the Technical Information Manual (NOT the Workshop manual) starting on page 116. Sounds like you need to go through ALL of them.

[David T]

You have certainly been busy and spent a LOT of money! Many of the things you did should have had no effect on the motor but some could have, especially if you did anything wrong. At this point I would start like it is a new problem and start from the beginning. Recheck and make sure the spark plug wires are wired correctly to the firing order. Recheck the gaps on the spark plugs and both ends of each of the wires are snapped on. Check the timing and vacuum advance. Check the duty cycle to the Frequency valve. Check for vacuum leaks, a smoke machine would be useful if you have one or can borrow one. Is the factory tamper-proof plug still in the mixture unit? If it isn't, your mixture adjustment could be way off. A bad ignition coil is a possibility, especially if it is an "aftermarket" one. Another possibility is a bad impulse coil but they typically fail completely when they go bad (not make the engine run bad). Recheck the routing of your vacuum hoses. When the motor warms up it affects the vacuum advance so if you don't have things hooked up correctly it *could* produce the symptom you have although you do have an unusual symptom. Generally when you wind up with an unusual symptom it often means either you have a bad part that failed in an unusual manner or you hooked something up wrong. Did it run OK BEFORE you worked on it? If it did not (or you just never ran it enough to know) then this could be an old problem and not related to anything you did. I have seen old cars sold because they had problems and no one could figure them out so the owner sells it to get rid of the problem.

[Ron]

The symptoms sound like the fuel return line may be partially blocked, preventing the WUR/CPR from bleeding off pressure, keeping the control pressure too high. I've seen where a broken piece of PPR o-ring in the FD return port did the same thing.
Like Andy said, you need to use the proper gauge set for the fuel pressures if you haven't (and perform all of the other tests in the manuals).