mattdott

I bought a 1988 crx Si with an ls/vtec , converted to obd1.

When I was driving home one day, the car goes into limp mode. I shut off the car and fire it back up and its fine. Over the next few weeks , it goes into limp mode a few more times. I decided to check out the wiring, the conversion harness looks hacked up, so I buy a new conversion harness and p28. After I install them I have a hard time starting the car. It finally fires but is throwing a code for map sensor. It won't run right unless I unplug the map sensor then.it will idle.

But I cannot hit the gas. It bogs and dies. It's throwing a code number 9. The sensor ohms out right and I ran new wires straight to the ecu. Still code 9. Still will not stay running.

Here is what I have tried.

2 differant p28's, multiple chips.
2 differant distributors.
Fuel pump
Fuel.pressure reg.
2 map sensors.
2 differant obd0 to 1 harnesses.
Plugs
Fuel filter.
Multiple main relays.
Tps checks out to .52 volts.
Map sends 5.2 volts when engine off.

The car will only rev up if you play with the throttle and evem then dies.
But if the map sensor is unplugged it will idle for about 30 seconds then die. Plugged in it will not idle and will barely start.

The only code I'm getting is 9. And it checks out and I have ran new wires.

Please help.

mattdott

Anybody have any ideas.. I'm stumped.

turbohatchBnuts

on the jumper harness check the pin to the ecu. I had a jumper harness once and the solder broke on the jumper harness causing my car to throw cel codes. I had to resolder the pin on the jumper harness. you will need a pin out for obd0 and obd1 ecus. then make sure it has a good connection were it plugs up at on the jumper harness.

mattdott

Thanks for the responce.

I have tried multiple harnesses and even wired staight to the obd1 side on the harness direct to the dizzy. I have continuity from dizzy plug to ecu plug.

Any other ideas. ? I'm totally lost.

mattdott

I have had code 9 since I bought the car. The no start issue has just started. I just need to get to work.

mattdott

Come on guys, your the pro's. I cant figure this out.

4drEF

So you ran wires straight from the distributor to the ECU and still get the same code.

Either -

The obvious
1) you ran the wires incorrectly
2) Your distributors might be messed up. Verify working condition on a different car.

The not so obvious
1) Bad valve stem seals allow excessive oil in the combustion chamber.
2) Distributor Cap.
3) Distributor Rotor.
4) Spark Plug Wires.
5) Ignition Timing.

mattdott

Both distributors work in another car.

Triple checked wires, sensor ohms out perfect.

Engine does not burn any oil, less than 10k miles on rebuild.

Different plugs, wires, cap, rotor, and timing belt is dead on.

Why does the car idle when i unplug the map sensor??

Should i run new wires for the MAP?

turbohatchBnuts

try another map sensor. have you already done that?

mattdott

Yes sir, I have tried 2. Both good maps. One throttle body mounted, one firewall mounted. Same result. It will not idle and dies completely if I touch the gas. I'm stumped.

That's why I'm here. I cam usually search and find the answer but this is crazy.

turbohatchBnuts

do you have a distributor jumper harness to or did you make your own? cel 9 is cylinder position sensor and is inside your distributor. either the sensor is bad or the wiring is incorrect or lacks continuity.

mattdott

I have 2 sets of distributor jumpers ... Tried both. The sensor ohms out to 390 ohms...within spec. Ran pin 4 and 8 of the distributor plug to the ecu. Still have code 9. I have did this on both dizzys.

Anybody have any other ideas? I'll pay a reward to the.man that figures this out..

DCRB

are the two wires reversed? how about the tps and map sensor plugs are they plugged into one annother?

mattdott

I switched the Tps and map, just to see, no change. I can try to switch the wires I ran, but i triple checked them aleady.

turbohatchBnuts

the tps sensor is going to be on the engine harness and the map sensor is on the cabin harness coming out of the firewall.

turbohatchBnuts

is it a orginal si or has it had a mpfi conversion?

B18B1-Crx

not trying to be a dick but sounds like your out of gas? bad fuel
sending unit?

think of the moment it went into limp mode? engine load temp speed etc

Doesn't the ecu ground on the t stat? Check that as well

is your timing right because it is know to throw random codes when off

mattdott

It's an original Si.

mattdott

I changed the fuel pump when this happened. Plenty of gas in the tank.

The car would go limp at random times and now will not start.

Timing is perfect on the belt. I don't know where exactly the dizzy is because it ain't stay running.

mattdott

Ok guys , I plug in a p0a accord ex vtec ecu. It starts and idles. But it choked out when i hit the gas.

I don't know if this help at all.

mattdott

Ok with the P0a accord ecu, I changed the obd0-obd1 coversion harness for a new one. It runs. I drove it .

But run horrible, and now I am getting code 8.

What should my next step be? I'm running out of money. I can keep buying parts.

Two different distributor codes with multiple distributors, and multiple ecu's.

ef_cowboy

are ALL the fuses good?

ef_cowboy

http://www.corpusracing.com/communit...-you-will-need
it shows all the codes there.
it says 8 is tdc and 9 is cylinder sensor...so i would put the first computer back on and look, check, rewire, or what ever the wires to the distributor.... .02$

00PhillySi

Any recent news on a fix for this problem? I have an LsV swap in my em1 that has been running for months with no problems until I went out to start it yesterday and it did the same thing as your crx, it starts up for 2 seconds then dies and if i hit the throttle it dies even faster.
But I unplugged the map sensor plug and it started up and idled like normal, then when i rev'd it up a bit it died when it came back towards idle i think because it flooded. So now while I'm waiting for the engine to clear out I'm trying to find any info at all on what to do to fix this.

Also when i switched my TPS and MAP plugs it would start up and idle like normal, but if I hit the gas it bogs and went into limp mode and wouldnt let me rev past 2k rpm

Any info would be greatly appreciated

CRX-Kid11

i know this is an old thread but im having the exact problem with mine, wondering if the issue was ever resolved?