DDT info

**mercrazy** · 09-26-2008, 08:42 AM

when testing A49 with DDT tester, how do you know if the box is good? in the manual, it just talks about checking MAP sensors, air temp, etc. How do you know if the box is good?

**Jay Smith** · 09-26-2008, 08:57 AM

I find most of the time when I find a BAD box the DDT ( OTC 4000 ) will signal "No SIGNAL FROM ECU "

hope that helps,
Jay

**mercrazy** · 09-26-2008, 09:21 AM

Jay, i hate to keep bugging you, but if my box performs perfectly except for warm startups, what would i look for on the DDT? Thanks

**Jay Smith** · 09-26-2008, 09:32 AM

Not bugging me at all, we all ( including ME ) learn from all the great information and sharing from prior experiances...

1st are the injectors clean lately ? ( By Brucato )
2nd do you have a fuel pressure gauge attached ?
3rd when you cut pump off does the pressure drop to zero quickly ?
4th do you feel your"issue" a rich or lean condition ?
5th is your battery HOT and not running at 12.5 or more volts
6th at 1500 rpms is your voltage 14 vbolts or MORE ?

Give me a call at my cell 1 281 798 3150 cst I'd be glad to maybe "cuss and discuss" your issue..I'm here now ! 9:30 am CST

Jay

**mercrazy** · 09-26-2008, 09:46 AM

1. yes by brucato
2. yes, holds 40lbs. consistently. i've tried 2 regulators.
3. it drops quickly to 5lbs., then slowly to zero.
4. rich, smokes immensely when it finally starts.
5. yes, i've tried it from 11.8 up to 13 volts.
6. i haven't checked that. it starts perfect at any voltage until i let it run for 10 minutes. how would this affect startup? does the box know if the voltage regulator is bad?

**Jay Smith** · 09-26-2008, 10:04 AM

If the voltage is spiking up and down it will have an adverse effect on the ECU as in a perfect world it ( the ECU ) "needs" consistant voltage..

Jay