Limp Home Mode, no codes?

Hello,

This sounds like the throttle bore is dirty causing the limp mode because the PCM loses correlation with the throttle actuator here is a guide to help us fix it.

https://www.2carpros.com/articles/reduced-power-limp-mode


Please run down this guide and report back.

Thanks for this post I had this problem and the guide help me fix it I love this site.

For several days my Honda has experienced something I've never heard of before. The first time this incident began was when I was in rush hour going home. At some point during the slow traffic my engine light turn on and I noticed my car took a harder push to the gas pedal to accelerate. When i was able to get free my car could only go a top speed of 30 mph. No matter if I pressed on the gas harder it wouldn't go. So I had to leave my vehicle at a friend's house. The next day I went to go check my car out and when I turned it on the engine light had turned off and it was like nothing ever happened. I drove it home with a very confused thought. Over the days I noticed either during traffic or prolonged periods of driving this will occur. Light will turn on and my gears will switch back from 5 to like 3. I did some searching and found my problem could be my Top Dead Center (TDC) sensor. Most people with similar problems report of the same thing. Supposedly the cause of my problem would be that my computer is receiving an incorrect signal from my tdc and it forces my car into "limp mode" to where the vehicle could only go a certain speed to not harm the engine but able to get off the road. Is this my real problem or something else?

It sounds like we need to run the codes here is a guide to help.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please run down this guide and report back.

replaced radiator, reconnected radiator hoses and transmission cooler lines. snapped on all connectors. topped off transmission with OEM Honda fluid. Next day limp mode with no cruise control. Bench tested a b solenoid both clicked proper ohms range. Screen perfectly clean. Fluid replaced two months prior four three quart drain and refill refills twelve total no back flush. I know it is electrical but does this point to a particular sensor. Sprayed and cleaned all connectors with electric contact cleaner. Do not know what I missed.

recheck your work replacing a radiator should set a code. then check fuses under hood.

checked everything and no codes. Are there soft codes my scanner would not see?could I have damaged a sensor with electricity meaning not physical damage? Would reversed transmission coolant hoses cause a problem? How can I check each sensor and find resistance values with and ohmmeter? How do I find out the voltage present on the wiring harness connectors and what the exact voltage at the connectors should be?

most sensors operate on five volts. the only sensors you can check for resistance is ect it will be high at around seventy two degrees and go down to less than 1000 at temperature. I think you are shooting your self in the foot looking for this see if you can get the soft codes to pull up reversed coolant lines would only send transmission oil in different direction or would not at all as one side is pressure other is not. not sure if it would or not as no pressure would mean overheating in transmission. try reversing see if it clears up. surprising that there are no codes in limp there should be.

pulled codes. cleaned all connectors. Deleted codes. Haven't come back for 2 weeks. Silly me. did not write down codes. Thought they would come back. D light was flashing did not come back. Saw in Honda forum limp mode and no cruise is electrical. Bad connection or sensor. Trying to pinpoint that sensor with these symptoms. Have and ISS OSS VSS TCC to many to list. I did disconnect the Input shaft speed sensor in the front of the transaxle. Wonder if I could have shorted the sensor. Others were disconnected to make clearance for cooling fan removal and radiator removal.

good morning

you cannot short out sensors. it may be more of a bad connection. make sure there is no damage to the pins or connector.

Roy

hi,
I have a 2002 ep3 civic,a while back the gearbox went so we got a used one off the dealer I originally got the car from. a friend installed if for me and ever since then the car ran in limp mode, after 5 months the limp mode stopped and recently came back on, however this time limp mode only comes back on after i hit a bump, the D symbol will flash and the engine light comes on at which point limp mode will be engaged.

Could you advise me on this as no mechanic near me can figure out the issue. I should also point out since the new gearbox the P-R-N-D-D2-D1 sequence doesnt line up on the gear stick and the dials.there is also a slight burning smell under the hood, this may just be common with this car and not an issue.

Im desprate to get to the bottom of this as i need the car for work and im waiting for the day it goes too far and dies altogether.

thanks,

Cormac

check your wiring if this hits a bump and works then it's pretty much a ground issue it sounds like to me. or a bad plug going into trans. we donlt list an ep2 in our manual only a dxexgx, etc. and it 's for a 1.7L but the ground is in middle of engine. as far as your shift things not lignin up you may need to readajust the cable so the range selector can line up. ican't copy the procedure for shift cable adjustment sorry

thanks for the reply, It happended the other day after a long drive and has been happening everytime i hit a bad bump since then,Its lowered on real stiff sport springs so when it hits a bump it hits hard. is there any easy way i could check any of your suggestions myself as i am not a mechanic?
thanks

this is the car

none of your pics came out so I have no idea anyhow as I'm not real familiar with Hondas. is it like a gx/ex etc. regardless the ground should be the same anyhow. Yes look in middle of engine front and back to see if there is aharness bolted to block or that the plug in trans is all the way in. see if it's loose or plug is connected well or broken wires.

Hi everyone,

This is my 1st post, may I say hi to you all!

Hope you had a Merry Xmas & looking forward to a Happy New year!

(& thanks in advance for any info that you help me out with..)

What I have: 2001 5 door, 1.4 automatic Honda civic

*which had light front damage (panels etc now repaired)

Basically I bought this car, as a salvage vehicle partly repaired! with 33k on the clock, Looking like a Bargain I bought it home, as it only looked like it needed an Airbag kit... (Which I have bought Already consiting = 2x front airbags , 2x seat belts pretensioners & the Airbag control module! BUT NOT FITTED YET)

The car is stuck in Limp mode / safety home mode, the check engine light is on along with the airbag light!

when I turn the car on for the 1st 30secs the ecu clicks with the MIL/check engine light flashing, after it performs its self check, the car then goes into limp mode, it is an automatic so it starts holding higher gears, & stops reving over 3000rpm

*within the 30 secs, it runs sweet as a nut! goes through all the gears, & revs all the way*

I have had it plugged in to 3 different obd2 scanners (& knowing it needs airbags & its control module resetting or changing), But its not reading Any error codes out atall! Which is worrying, Does this always happen to honda's? or is it just mine? unfortuntantly the cars not communicating with any OBC II code reader i use?

Now i am thinking if the ecu is working properly or not?

As the code readers work on other cars, expect for mine!

& Does the main car ecu & the airbag control ecu/module need to be programmed TO each other?

Has anyone replaced such parts in a 2001 honda civic (mine is a uk spec)?

or had the same type of problem?

what do I need to do to get it out of Limp mode? IS limp mode even connected to the airbag srs system in anyway?

I am wanting to confirm before I go ahead & fitt the airbags & even have any work done on any of the 2x airbag ecu's I have
dont want them to go off when i turn the car on LOL!

I have only tried to get the codes from the obdII plug, not the paperclip way?
& is there any way to test the airbag ecu in th car 1st without using airbags? (using the 2ohm resister bridged theory on the airbag plugs & tensioners?)

Thanks alot.Bandoliero

Posts: 1
Joined: Mon Dec 28, 2009 2:22 am
Private message

Hi Bandoliero,

If the scanner cannot communicate with the PCM, the most likey fault is a bad PCM.

You can try if the paper clip works. Bridge terminal # 4 and # 9 to see if it works.

Air bag is not related to the PCM and when the air system fails, the engine should perform as normal, only nuisance would be the airbag indicator light staying on all the time.

The PCM( ECU ) should self check for only 2 seconds and you mentioned 30 seconds meaning a fault is ever present.

Thanks im goin to have a look at that in the morning,if you google ep2 type r white it will come up.
Il be sure to let you know how I fair out.
Thanks

I today installed the airbags & seatbelts with pre-tensioners, & hooked up the NEWER airbag ecu I bought, With the airbag kit!

The SRS lights still on, & YES your right, the cars still in Limp mode!

YES in the 30 seconds the Check Engine Light flickers with the sound of some relays, Once the fault is not resurected the Check engine light comes on intermittantly, & its then the car goes into limpmode!

Do you think the AIRBAG ECU & CAR ECU have to be programmed to each other?

(I have my old airbag ecu with crash data stored, I suppose I could have that cleared of its errors & re-use that to see it clears the srs light? As it should already be programmed to my car?)

the info I sent to you is correct it is like a Honda civic gx.

There was a blue plug on the top/front that was not in the whole way,i plugged it in but i have no way of knowing if it worked or not until i hit a bump again,the check engine light is still on though

you will need a scanner to remove the check engine light an autoparts might do it for you.

hi,
I went out this morning and the car wont start, just two small click from the starter motor, Do i need a new starter or is this a battery issue?

I really appreciate the help as the last info you gave me worked a treat.!

Thanks,

Cormac

So i was driving my car the other day, accelerating onto the highway walking the RPMS up, and all of a sudden my car is starving. It begins to flutter, Battery light comes on, Key light comes on, and i can't do much more than coast to a safe spot off the highway. its as if my car was starving to breath. I pulled over, turned ff the car and checked to see if my Hood support stick hit my battery terminal and shoprted the system. I inspected all my connections, nothing was out of place and started the car up again. This time, the battery light went off, The Check engine light came on, i had no Power to the Tachometer, no power to the Engine Temp gauge and my car was idling in limp mode. I couldn't rev it past 3,000 rpms. I know this because i heard the bearing spin and makes a slight noise when it hits 3,000 RPM.


I was stumped. I drove the car home in side streets in limp mode, moving slower than a turtle.
I called up my buddy with a scan tool and We scanned the car and its said "NO LINK" .
This was funny. so i decided to take the Car to Auto zone, I drove there in limp mode, slowly. While driving on the highway i shut off the car, turned it off, back on, popped the clutch in gear and started the car, Intermittently the car would be ok, check enigine light will flash for a sec, the car would bog, then go back to normal, do this about 5-6 times and then finally stay in limp mode. during this time the Tach and Engine temp are working fine.
I also performed a Instrument Cluster check and all my gauges swept across indicating a perfect cluster.

SO when i got to AutoZone we scanned this again and the code reader said "Check connections"

Thinking it was a computer issue i replaced the PCM, THE Multiplex Control Unit, even the Ignition control switch, and nothing has fixed it.


I am completely lost on where to diagnose this problem next. Where do i go from here?

Hi 01bluCivicEX,

Start by checking the connectors at the PCM. Look out for contaminations and looseness.

check battery for condition including load test autoparts can do this for free as well as tire stores. if battery is bad or low it will cause your problem but cold be a starter as well. test battery first though

Ditto Check, Nothing is going on.

Hi,i got the battery checked and it was flat but had enough power for lights etc,but the problem still persists,i have knocked the starter with a hammer with no joy,checked all the fuses and cleaned the battery terminals.
Would you know the next course of action i should take?
Thanks,

Cormac

At the DLC, test terminal # 16 for battery voltage and terminal # 4 fo continuity to ground.

what do yo mean the battery is flat if it reads below 12.4 volts then it's trash probably. I told you autoparts check these for free and they can seeif you charging system is charging as well. this needs to be scanned which I'm sure I've mentioned in the past. Looks like you are doing things half assed and trying to get it going. I have no further suggestions.

Checked. There is voltage to the terminal, and there is Continuity.

I did bring it to an auto place to have it checked and they told me it was flat so i got a new one.

Use a jumper wire to bridge terminal # 4 and # 8. Turn ignition switch on, check if the CEL is blinking any codes.

I recently did a timing belt and water pump on my civic. About a week after I did it I was driving and all of a sudden the engine jerked and it went into limp home mode. I rechecked timing and everything is all good, but now I can't communicate with the vehicle using a scantool to figure out what is goin on. All of the connectors for the cam sensor and crank sensor are good. What the heck is going on???

just to confirm, the #8 Terminal , what color wire is it?

Hello,

There is a fuse #9 (10 amp) in the under hood fuse panel which runs the ALDL lets check that first here is a wiring diagrams for the connector so you can make sure it is all connected.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Here are the fuse locations. Check out the diagrams (Below). Please let us know what you find. We are interested to see what it is.

Ok i used a wire to connect #4 to #8 and there was no action on the CEL ...

ok, got the code. P0335 Crank Position sensor cicuit malfunction. I thought it might be this code, so last night i inspected the plug connector going to the sensor and it looked ok. I really didn't look to closely though, there may be pins corroded or bent but it pluggd in nice and easy so I didn't think much about it. I mainly checked to see that the wiring hadn't come loose and into contact with the crank pulley and casued a short, but that didn't happen. Could it be the crank sensor, they aren't to complicated, just a simple hall effect. oh yeah, I forgot to mention, the timing had jumped one tooth somehow. Could this have damaged the sensor somehow when it did jump?

Sorry for the error, the terminal should be # 4 and # 9.

I will send you the diagnostic procedures for diagnosing the DLC.

If the timing is off, that could set the code because it wasn't in synch with the cam sensor. The crank sensor supplies the reference signal for both ignition and injector pulse so it wouldn't run without a Crank signal.