Copeland

iTrader: (42)

93 VR Automatic.
-dp
-hiflow cat
-catback
-intake
-xspower smic
-greddybov
-turbotimer
-brand new spark plugs
-good gas
-wastegate/precontrol is also wired for 7psi currently

I know this is a very common problem with FD's but I am kind of baffled by this particular issue. My friends FD blew a PD out and caught the engine on fire but got it put out rather fast. I have rebuilt the top end (used parts in place of melted pieces, IAT still there from fire, rest is in good shape) and maybe a sensor went bad or something but I have generally all good working parts in there now. It will start and run on a PFC but will not even start with the stock ECU. I have been kind of confused as I have tried three different sets of coil packs (I had extras), new wire harness (used), and lots of other things. It is not flooded as it will start easily on the PFC but not the stock ECU. I have checked all the vacuum lines lots of times and none are loose or missing. I am just curious to as what everyone thinks it could be. I will try to answer any other questions or suggestions you have. Thanks

So when the car starts on the PFC and it runs decently but still smokes (although less) above 2000rpms. It is very choppy and sounds like it is missing at any rpm. It is horribly rough at ~800rpms like its going to stall. It will smoke worse until it is warmed up but it still continues to run horribly. The cat all the while gets excessively hot so I am thinking maybe it's running really rich. The cat is not clogged bc it runs the exact same without it. It will start on my old automatic ecu very rarely but not the original ecu in the car. The PFC will help a lot but sometimes it will still flood. I did however get a lot of white smoke during one start but have not since or before had it happen again. It is mostly black or grayish smoke. Smells like rotary/fuel.

I will do a compression check but the engine only has 25k miles on it and supposedly rebuilt by a reputable shop but I do not know how true this statement is or if it was even rebuilt. The previous owner also said it was a R1 converted to automatic but the carpet is tan and the entire interior was converted to black but the carpet and the rear trunk cover thing is tan too. It could be possible but VERY VERY unlikely. I have not told the current owner though.

Again thanks for any contribution! Sorry if it's a bit choppy.

2FAST7S

is the intake air temp hooked up and working? A cold reading will tell the ecu to dump way too much fuel(red cat, choppy idle, smoke, flooding).

find a way to check the stock ecu, I think it might have gotten damaged during the fire.
Hope this helps!

dradon03

iTrader: (2)

First thing to check would be the MAP sensor.

Copeland

iTrader: (42)

Lol I was wondering how long it would be before someone came in with the ol' map sensor check. I'm going to put some new injectors in it and check everything and get back to you all. Thanks for all your help so far.

Copeland

iTrader: (42)

Alright I know for certain the IAT is hooked up properly and is working. The MAP sensor works fine and is definitely hooked up right. Is there any change the fuel injectors may have been damaged in the fire? Do you think it could be the idle motor with the white clip and two wires? I put a different one on but found one of the wires came out the clip. Thanks if you have any other ideas.

Copeland

iTrader: (42)

Well I drove it again today but I'm going to tear it apart again it ran horrible under any load at all. It would not get into boost at all let alone roll. Hard to describe but it was stumbling and then it would run like **** on idle. It smoked up lots of white smoke but it went away after about 5 minutes and just black/gray smoke from there.

Albe's G

Did you check the TPS?

Copeland

iTrader: (42)

Any more ideas?

Copeland

iTrader: (42)

The entire top end of the engine was completely reassembled and all the vacuum lines were reran and all the wiring patched. The injectors were cleaned and the TPS was replaced and adjusted. It has a new set of coils on it and it still has hot start problems and it runs like it's missing. I had it running decently before so I know the coils are good. Tthe plugs are fresh. The MAP sensor is hooked up properly and the IAT is too. I have all the coolant sensors and fuel connectors hooked up properly. It has no vacuum leaks and the ECU is the proper one and is connected right. It has no check engine codes and still retains all of the emissions equipment with the exception of the air pump. The fuel pump works properly and is supplying the correct pressure and receiving the correct voltages. Anyone have any ideas?

Compression was supposedly above 90 on both rotors.

R3DLINE

iTrader: (1)

I second that.
The pesky MAP sensor is prone to lose the vacuum line time to time. Mainly because of the way it's located - upwards.

Had happened to me in the past.

djseven

iTrader: (56)

Sounds like a small peice of apex seal is gone. If the housings are in good shape the motor will still make enough compression to run even with a blown engine. Just wont run under load and will constantly black smoke. What is vacuum reading at 850-900 rpms? Im assuming down around 8-10 and possibly bouncing slightly? If you dont have a boost gauge what is the vacuum reading on teh PFC in mmhg?

xzl6b1

iTrader: (7)

Same problem. Started to run very rich. Compression is above 90 psi on all 3 faces, both rotors. Was runnimg about 15 in hg vacuum now 8-10. Engine surges at steady 2500 rpm.

Both rotors are running rich. car had been sitting for a long time, I just changed the fuel pump and filter, drained/refilled gas tank.

If the apex seals are shot, I may just sell the car.

sctRota

iTrader: (2)

Map sensor is ringing all the bells atm
Swap the sensor with another one OR try a GM 3 bar map (remember to change the PIM settings in the datalogit)

I had a cracked check valve on my boost sensor that seeped on idle but didn't leak on applying the accelerator.

If that doesn't work, I suggest checking to see if your water temp sensor is working. if the voltage is faulty, it can cause an extreme rich mixture and will not let you rev, idle and/or boost.

nguybao

iTrader: (6)

Have you checked your O2 sensor? Turned off feedback on the PFC?

The fact that it runs with the PFC and another auto ECU leads me to believe the original ECU is damaged.

Copeland

iTrader: (42)

Wow, talk about an old thread.

The owner of the car didn't want to spend any money on the car so they sold it to someone else for super cheap. No idea what the issue was but the car was a hack job so it could have been anything.